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Salais-López H, Agustín-Pavón C, Lanuza E, Martínez-García F. The maternal hormone in the male brain: Sexually dimorphic distribution of prolactin signalling in the mouse brain. PLoS One 2018; 13:e0208960. [PMID: 30571750 PMCID: PMC6301622 DOI: 10.1371/journal.pone.0208960] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 11/27/2018] [Indexed: 01/10/2023] Open
Abstract
Research of the central actions of prolactin is highly focused on females, but this hormone has also documented roles in male physiology and behaviour. Here, we provide the first description of the pattern of prolactin-derived signalling in the male mouse brain, employing the immunostaining of phosphorylated signal transducer and activator of transcription 5 (pSTAT5) after exogenous prolactin administration. Next, we explore possible sexually dimorphic differences by comparing pSTAT5 immunoreactivity in prolactin-supplemented males and females. We also assess the role of testosterone in the regulation of central prolactin signalling in males by comparing intact with castrated prolactin-supplemented males. Prolactin-supplemented males displayed a widespread pattern of pSTAT5 immunoreactivity, restricted to brain centres showing expression of the prolactin receptor. Immunoreactivity for pSTAT5 was present in several nuclei of the preoptic, anterior and tuberal hypothalamus, as well as in the septofimbrial nucleus or posterodorsal medial amygdala of the telencephalon. Conversely, non-supplemented control males were virtually devoid of pSTAT5-immunoreactivity, suggesting that central prolactin actions in males are limited to situations concurrent with substantial hypophyseal prolactin release (e.g. stress or mating). Furthermore, comparison of prolactin-supplemented males and females revealed a significant, female-biased sexual dimorphism, supporting the view that prolactin has a preeminent role in female physiology and behaviour. Finally, in males, castration significantly reduced pSTAT5 immunoreactivity in some structures, including the paraventricular and ventromedial hypothalamic nuclei and the septofimbrial region, thus indicating a region-specific regulatory role of testosterone over central prolactin signalling.
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Affiliation(s)
- Hugo Salais-López
- Unitat Predepartamental de Medicina, Facultat de Ciències de la Salut, Universitat Jaume I, Castelló de la Plana, Spain
| | - Carmen Agustín-Pavón
- Unitat Predepartamental de Medicina, Facultat de Ciències de la Salut, Universitat Jaume I, Castelló de la Plana, Spain
- Departament de Biologia Cel·lular i de Biologia Funcional, Facultat de Ciències Biològiques, Universitat de València, València, Spain
| | - Enrique Lanuza
- Departament de Biologia Cel·lular i de Biologia Funcional, Facultat de Ciències Biològiques, Universitat de València, València, Spain
| | - Fernando Martínez-García
- Unitat Predepartamental de Medicina, Facultat de Ciències de la Salut, Universitat Jaume I, Castelló de la Plana, Spain
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Ochoa-Amaya JE, Hamasato EK, Tobaruela CN, Queiroz-Hazarbassanov N, Anselmo Franci JA, Palermo-Neto J, Greiffo FR, de Britto AA, Vieira RP, Ligeiro de Oliveira AP, Massoco CDO, Felicio LF. Short-term hyperprolactinemia decreases allergic inflammatory response of the lungs. Life Sci 2015; 142:66-75. [PMID: 26477293 DOI: 10.1016/j.lfs.2015.10.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2015] [Revised: 10/11/2015] [Accepted: 10/14/2015] [Indexed: 01/24/2023]
Abstract
AIMS Prolactin is a major immunomodulator. The present study evaluated the effects of short-term hyperprolactinemia induced by domperidone before ovalbumin antigenic challenge on the lung's allergic inflammatory response. MAIN METHODS To induce hyperprolactinemia, domperidone was injected in rats at a dose of 5.1mg·kg(-1) per day, i.p., for 5days from 10th to 14th day after OVA immunization. Total and differential leukocyte counts from bronchoalveolar lavage (BAL), femoral marrow lavage (FML), and blood were analyzed. The percentages of mucus and collagen production were evaluated. Levels of corticosterone and prolactin in serum, interleukin-4 (IL-4), IL-6, IL-10, tumor necrosis factor α (TNF-α) in lung explants supernatants were measured and interferon gamma (IFN-γ) in bronchiolar lavage cells suspensions (BAL) was measured. KEY FINDINGS The rats that were subjected to short-term hyperprolactinemia exhibited a decrease in leukocyte counts in bronchoalveolar lavage, cellularity decrease in femoral marrow lavage fluid, a lower percentage of mucus, and an increase in lung IL-4, IL-6, IL-10, TNF-α and IFN-γ expression. SIGNIFICANCE Hyperprolactinemia induced before antigenic challenge decreased allergic lung inflammation. These data suggest that prolactin may play a role in the pathophysiology of asthma. The present study demonstrates a prospective beneficial side effect of domperidone for asthmatic patients.
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Affiliation(s)
- Julieta E Ochoa-Amaya
- Departamento de Patologia da Faculdade de Medicina Veterináriae Zootecnia da Universidade de São Paulo, São Paulo, SP, Brazil; Facultad de Ciencias Agropecuarias y Recursos Naturales, Programa de Medicina Veterinaria y Zootecnia, Universidad de los Llanos, Villavicencio, Colombia
| | - Eduardo K Hamasato
- Departamento de Patologia da Faculdade de Medicina Veterináriae Zootecnia da Universidade de São Paulo, São Paulo, SP, Brazil
| | - Carla N Tobaruela
- Departamento de Patologia da Faculdade de Medicina Veterináriae Zootecnia da Universidade de São Paulo, São Paulo, SP, Brazil
| | - Nicolle Queiroz-Hazarbassanov
- Departamento de Patologia da Faculdade de Medicina Veterináriae Zootecnia da Universidade de São Paulo, São Paulo, SP, Brazil
| | - Janete A Anselmo Franci
- Laboratório de Neuroendocrinologia da Reprodução, Universidade de São Paulo, Faculdade de Odontologia de Ribeirão Preto, São Paulo, SP, Brazil
| | - João Palermo-Neto
- Departamento de Patologia da Faculdade de Medicina Veterináriae Zootecnia da Universidade de São Paulo, São Paulo, SP, Brazil
| | - Flavia R Greiffo
- Programa de Pós-Graduação em Biofotônica Aplicada às Ciências da Saúde, Universidade Nove de Julho, São Paulo, Brazil
| | - Auriléia Aparecida de Britto
- Programa de Pós-Graduação em Biofotônica Aplicada às Ciências da Saúde, Universidade Nove de Julho, São Paulo, Brazil
| | - Rodolfo Paula Vieira
- Programa de Pós-Graduação em Biofotônica Aplicada às Ciências da Saúde, Universidade Nove de Julho, São Paulo, Brazil
| | - Ana P Ligeiro de Oliveira
- Programa de Pós-Graduação em Biofotônica Aplicada às Ciências da Saúde, Universidade Nove de Julho, São Paulo, Brazil
| | - Cristina de O Massoco
- Departamento de Patologia da Faculdade de Medicina Veterináriae Zootecnia da Universidade de São Paulo, São Paulo, SP, Brazil
| | - Luciano F Felicio
- Departamento de Patologia da Faculdade de Medicina Veterináriae Zootecnia da Universidade de São Paulo, São Paulo, SP, Brazil.
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Abstract
Prolactin (PRL) has been long deemed as a hormone involved only in female reproduction. However, PRL is a surprising hormone and, since its identification in the 1970s, its attributed functions have greatly increased. However, its specific role in male health is still widely unknown. Recently, low PRL has been associated with reduced ejaculate and seminal vesicle volume in infertile subjects. In addition, in men consulting for sexual dysfunction, hypoprolactinemia has been associated with erectile dysfunction and premature ejaculation, findings further confirmed in the general European population and infertile men. Several metabolic derangements, recapitulating metabolic syndrome, have also been associated with low PRL both in men with sexual dysfunction and from the general European population. In men with sexual dysfunction, followed-up for more than 4 years, low PRL was identified as an independent predictor of the incidence of major adverse cardiovascular events. Finally, an association with anxiety or depressive symptoms has been found in men with sexual dysfunction and from the general European population. While a direct role for impaired PRL function in the pathogenesis of these reproductive, sexual, metabolic and psychological disorders is conceivable, the possibility that low PRL is a mirror of an increased dopaminergic or a decreased serotonergic tone cannot be ruled-out. Hyperactivity of the dopaminergic system can explain only a few of the aforementioned findings, whereas a hypo-serotonergic tone fits well with the clinical features associated with low PRL, and there is significant evidence supporting the hypothesis that PRL could be a mirror of serotonin in the brain.
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Affiliation(s)
- Giulia Rastrelli
- Sexual Medicine and Andrology Unit, Department of Experimental and Clinical Biomedical Sciences, University of Florence, Viale Pieraccini, 6, 50139, Florence, Italy
| | - Giovanni Corona
- Sexual Medicine and Andrology Unit, Department of Experimental and Clinical Biomedical Sciences, University of Florence, Viale Pieraccini, 6, 50139, Florence, Italy
- Endocrinology Section, Maggiore Hospital, Largo Nigrisoli 2, 40133, Bologna, Italy
| | - Mario Maggi
- Sexual Medicine and Andrology Unit, Department of Experimental and Clinical Biomedical Sciences, University of Florence, Viale Pieraccini, 6, 50139, Florence, Italy.
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Corona G, Wu FC, Rastrelli G, Lee DM, Forti G, O'Connor DB, O'Neill TW, Pendleton N, Bartfai G, Boonen S, Casanueva FF, Finn JD, Huhtaniemi IT, Kula K, Punab M, Vanderschueren D, Rutter MK, Maggi M. Low Prolactin Is Associated with Sexual Dysfunction and Psychological or Metabolic Disturbances in Middle-Aged and Elderly Men: The European Male Aging Study (EMAS). J Sex Med 2014; 11:240-53. [DOI: 10.1111/jsm.12327] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Iamsaard S, Prabsattroo T, Sukhorum W, Muchimapura S, Srisaard P, Uabundit N, Thukhammee W, Wattanathorn J. Anethum graveolens Linn. (dill) extract enhances the mounting frequency and level of testicular tyrosine protein phosphorylation in rats. J Zhejiang Univ Sci B 2013; 14:247-52. [PMID: 23463768 DOI: 10.1631/jzus.b1200287] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
OBJECTIVE To investigate the effect of Anethum graveolens (AG) extracts on the mounting frequency, histology of testis and epididymis, and sperm physiology. METHODS Male rats induced by cold immobilization before treating with vehicle or AG extracts [50, 150, and 450 mg/kg body weight (BW)] via gastric tube for consecutive 1, 7, and 14 d were examined for mounting frequency, testicular phosphorylation level by immunoblotting, sperm concentration, sperm acrosome reaction, and histological structures of testis and epididymis, respectively. RESULTS AG (50 mg/kg BW) significantly increased the mounting frequency on Days 1 and 7 compared to the control group. Additionally, rat testis treated with 50 mg/kg BW AG showed high levels of phosphorylated proteins as compared with the control group. In histological analyses, AG extract did not affect the sperm concentration, acrosome reaction, and histological structures of testis and epididymis. CONCLUSIONS AG extract enhances the aphrodisiac activity and is not harmful to sperm and male reproductive organs.
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Affiliation(s)
- Sitthichai Iamsaard
- Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.
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Ambhore N, Antony S, Mali J, Kanhed A, Bhalerao A, Bhojraj S. Pharmacological and biochemical interventions of cigarette smoke, alcohol, and sexual mating frequency on idiopathic rat model of Parkinson's disease. J Young Pharm 2012; 4:177-83. [PMID: 23112537 PMCID: PMC3483528 DOI: 10.4103/0975-1483.100026] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Parkinson's Disease (PD) is a neurodegenerative disorder in the nigrostriatal pathway of animals and humans and is responsible for most of the movement disorders, including rigidity. The present study aimed to determine the effect of chronic cigarette smoke, alcohol intake, and frequent sexual mating on 1-Methyl-4-phenyl-1,2,3,6-tertahydro pyridine (MPTP)-induced rat model of PD. After treatment, the effect of these factors was determined by biochemical and molecular evaluation. Dopamine (DA) concentration, antioxidant enzymes, and mitochondrial activity decreased after treatment with cigarette smoke, alcohol, and frequent sexual mating when compared to the values in the control group. Excessive exposure of these factors may lead to neurodegeneration, dopaminergic toxicities, and, ultimately, clinical parkinsonism. Earlier literature from different publisher suggested that nicotine and cigarette smoke can protect the dopaminergic neurons in the substantia nigra against MPTP toxicity. In this study, we assessed the effect of the above three factors on an MPTP-treated rat model and concluded that they have a neurodegenerative effect and were found to be toxic to dopaminergic neurons in the substantia nigra. Further investigation is required to understand the exact etiology of clinical parkinsonism.
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Affiliation(s)
- Ns Ambhore
- Departments of Pharmacology and Pharmaceutical Chemistry, Konkan Gyanpeeth Rahul Dharkar College of Pharmacy and Research Institute, Karjat, Raigad, India
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Galdiero M, Pivonello R, Grasso LFS, Cozzolino A, Colao A. Growth hormone, prolactin, and sexuality. J Endocrinol Invest 2012; 35:782-794. [PMID: 28726215 DOI: 10.1007/bf03345805] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/06/2012] [Indexed: 01/23/2023]
Abstract
GH and PRL, although not considered as 'classi cal' sexual hormones, could play a role in the endocrine control of sexual function both in men and women. Physiologically, PRL seems to be involved in the central control of sexual behavior and activity, by modulating mainly the effects of dopaminergic and serotoninergic systems on sexual function. Indeed, circulating PRL levels increase after orgasm and may potentially play a role in the acute regulation of further sexual arousal following orgasm both in men and women. On the other hand, either short-term or long-term PRL in crease can modulate central nervous system areas involved in the control of sexual function and, peripherally, can directly influence mechanisms of penile erection in men, and presently only as an hypothesis, mechanisms related to the sexual response of genitalia in women. Furthermore, chronic hyperprolactinemia is classically associated with hypogonadotropic hypogonadism and sexual dysfunction in both sexes. Successful treatment of chronic hyperprolactinemia generally restores normal sexual function both in men and women although this effect is not only related to relapse of gonadal function. Hypoprolactinemia is recently recognised as a possible risk factor of arteriogenic erectile dysfunction while a possible role on female sexual function is not known. The physiological role of GH on sexual function is not fully elucidated. GH is an important regulator of hypothalamus-pituitary-gonadal axis and seems to participate in the regulation of the sexual response of genitalia in men, and potentially also in women. Sexual function in men and women with GH deficiency (GHD) and GH excess, particularly in acromegaly, is scantily studied and GH- or IGF-I-dependent effects are difficult to quantify. Nevertheless, a decrease of desire and arousability both in men and women, together with an impairment of erectile function in men, have been described both in patients with GHD and acromegaly, although it is not clear whether they are dependent directly on the hormone defect or excess or they are consequence of the hypogonadism or the different clinical complications or the physical disfigurement and psychological imbalance, which are associated with the diseases, and are potentially affecting sexual function. Data on beneficial effects of GH replacement therapy and specific surgical or pharmacological approach for acromegaly are far to be fully elucidated although restoring normal GH/IGF-I levels have been associated to improvement of sexual function.
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Affiliation(s)
- M Galdiero
- Department of Molecular & Clinical Endocrinology and Oncology, "Federico II" University of Naples, Via S. Pansini 5, 80131, Naples, Italy
| | - R Pivonello
- Department of Molecular & Clinical Endocrinology and Oncology, "Federico II" University of Naples, Via S. Pansini 5, 80131, Naples, Italy.
| | - L F S Grasso
- Department of Molecular & Clinical Endocrinology and Oncology, "Federico II" University of Naples, Via S. Pansini 5, 80131, Naples, Italy
| | - A Cozzolino
- Department of Molecular & Clinical Endocrinology and Oncology, "Federico II" University of Naples, Via S. Pansini 5, 80131, Naples, Italy
| | - A Colao
- Department of Molecular & Clinical Endocrinology and Oncology, "Federico II" University of Naples, Via S. Pansini 5, 80131, Naples, Italy
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Weissheimer KV, Franci CR, Lucion AB, Sanvitto GL. The role of AT1 receptor-mediated reproductive function in renovascular hypertension in male rats. Horm Behav 2012; 62:43-9. [PMID: 22565127 DOI: 10.1016/j.yhbeh.2012.04.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2011] [Revised: 04/21/2012] [Accepted: 04/23/2012] [Indexed: 12/12/2022]
Abstract
There is an association between hypertension and reproductive dysfunction. Angiotensin II (Ang II) is involved in the pathogenesis of hypertension and the regulation of reproduction. The present study aimed to determine whether the angiotensinergic system mediates the effects of hypertension on reproductive function in male rats subjected to a two-kidney, one-clip (2K1C) model. Sexual behavior parameters, gametogenesis and plasma concentrations of Ang II, testosterone, prolactin and corticosterone were evaluated in male rats 28days after 2K1C or sham surgery and losartan (Los) treatment (a type 1 angiotensin II (AT1) receptor antagonist) or vehicle (V) treatment. The animals were divided into Sham+V, 2K1C+V, Sham+Los and 2K1C+Los groups. The 2K1C+V group showed a hypertensive response, inhibition of sexual behavior, spermatogenesis dysfunction, and increases in plasma Ang II and prolactin. Conversely, plasma testosterone decreased, and plasma corticosterone remained constant. Losartan treatment normalized blood pressure and prevented the changes in plasma testosterone and prolactin, sexual behavior and spermatogenesis in the 2K1C+Los group. In addition, losartan treatment caused an additional increase in circulating Ang ll in both groups (Sham+Los and 2K1C+Los). Together, these results suggest that Ang ll, acting through the AT1 receptor, modulates behavioral and endocrine parameters of reproductive function during renovascular hypertension. In addition, the effects of circulating Ang II on plasma testosterone and prolactin seem to contribute to the spermatogenic and sexual dysfunctions in hypertensive rats.
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Affiliation(s)
- Karin Viana Weissheimer
- Department of Physiology, Institute of Basic Health Sciences, Federal University of Rio Grande do Sul, Sarmento Leite 500, Porto Alegre, RS 90050-170, Brazil.
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Sukikara MH, Cruz AM, Felippe ECG, Anselmo-Franci JA, Canteras NS, de Oliveira CA, Felicio LF. Morphine-induced changes in opioid sensitivity in postpartum females: a unique progesterone response. J Neuroendocrinol 2011; 23:1134-8. [PMID: 21696473 DOI: 10.1111/j.1365-2826.2011.02182.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Opioid peptides play an important role in maternal behaviour, as well as in physiological and pathological phenomena involving motivation. Daily 3.5 mg/kg doses of morphine from days 17-21 of pregnancy are able to change the expression of maternal behaviour patterns. However, the role of hormones on such opioid behavioural actions remains to be determined. The present study investigated the endocrine responses to this morphine treatment. Corticosterone, progesterone, oestradiol and prolactin serum concentrations were measured after each morphine injection. No significant differences were found in corticosterone, oestradiol or prolactin serum concentrations. The results suggest that the treatment was unable to promote different effects, other than those caused by saline injections. In morphine-treated animals, however, progesterone concentrations were consistently and significantly increased from days 18-20 of treatment. Thus, because this behavioural meaningful opioidergic stimulation during late pregnancy affects progesterone levels, the findings of the present study raise the hypothesis that this hormone may play a role in morphine-induced changes in opioid sensitivity during late pregnancy and early lactation.
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Affiliation(s)
- M H Sukikara
- Departamento de Patologia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, Brasil
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Andersson KE. Mechanisms of penile erection and basis for pharmacological treatment of erectile dysfunction. Pharmacol Rev 2011; 63:811-59. [PMID: 21880989 DOI: 10.1124/pr.111.004515] [Citation(s) in RCA: 231] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Erection is basically a spinal reflex that can be initiated by recruitment of penile afferents, both autonomic and somatic, and supraspinal influences from visual, olfactory, and imaginary stimuli. Several central transmitters are involved in the erectile control. Dopamine, acetylcholine, nitric oxide (NO), and peptides, such as oxytocin and adrenocorticotropin/α-melanocyte-stimulating hormone, have a facilitatory role, whereas serotonin may be either facilitatory or inhibitory, and enkephalins are inhibitory. The balance between contractant and relaxant factors controls the degree of contraction of the smooth muscle of the corpora cavernosa (CC) and determines the functional state of the penis. Noradrenaline contracts both CC and penile vessels via stimulation of α₁-adrenoceptors. Neurogenic NO is considered the most important factor for relaxation of penile vessels and CC. The role of other mediators, released from nerves or endothelium, has not been definitely established. Erectile dysfunction (ED), defined as the "inability to achieve or maintain an erection adequate for sexual satisfaction," may have multiple causes and can be classified as psychogenic, vasculogenic or organic, neurologic, and endocrinologic. Many patients with ED respond well to the pharmacological treatments that are currently available, but there are still groups of patients in whom the response is unsatisfactory. The drugs used are able to substitute, partially or completely, the malfunctioning endogenous mechanisms that control penile erection. Most drugs have a direct action on penile tissue facilitating penile smooth muscle relaxation, including oral phosphodiesterase inhibitors and intracavernosal injections of prostaglandin E₁. Irrespective of the underlying cause, these drugs are effective in the majority of cases. Drugs with a central site of action have so far not been very successful. There is a need for therapeutic alternatives. This requires identification of new therapeutic targets and design of new approaches. Research in the field is expanding, and several promising new targets for future drugs have been identified.
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Affiliation(s)
- K-E Andersson
- Wake Forest Institute for Regenerative Medicine, Wake Forest University School of Medicine, Medical Center Boulevard, Winston Salem, NC 27157, USA.
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Ochoa-Amaya JE, Malucelli BE, Cruz-Casallas PE, Nasello AG, Felicio LF, Carvalho-Freitas MIR. Dual effects of hyperprolactinemia on carrageenan-induced inflammatory paw edema in rats. Neuroimmunomodulation 2011; 18:245-53. [PMID: 21430396 DOI: 10.1159/000323774] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2010] [Accepted: 12/22/2010] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES The effects of short-term 5-day and long-term 30-day hyperprolactinemia induced by domperidone (1.7 mg/kg/day, s.c.) or ectopic pituitary graft on the acute inflammatory response induced by carrageenan were evaluated in male rats. Both models of hyperprolactinemia effectively increased serum prolactin (PRL) levels. METHODS The volume in milliliters of inflammatory edema was measured by plethysmography 1, 2, 3, 4, 6, 8 and 24 h after carrageenan injection. The areas under the inflammatory time-response curves were compared. Additionally, the effects of hyperprolactinemia on body weight and serum corticosterone levels were evaluated. RESULTS In both domperidone-treated and pituitary graft-implanted animals, short-term 5-day hyperprolactinemia increased the inflammatory response, while long-term 30-day hyperprolactinemia had anti-inflammatory effects. Body weight was not affected by either short- or long-term hyperprolactinemia. CONCLUSION These results show that PRL has biphasic effects on the carrageenan-induced inflammatory response.
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Affiliation(s)
- Julieta E Ochoa-Amaya
- Patologia Animal, Escuela de Medicina Veterinaria y Zootecnia, Facultad de Ciencias Agropecuarias y Recursos Naturales, Universidad de los Llanos, Villavicencio, Colombia
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Gratzke C, Angulo J, Chitaley K, Dai YT, Kim NN, Paick JS, Simonsen U, Uckert S, Wespes E, Andersson KE, Lue TF, Stief CG. Anatomy, physiology, and pathophysiology of erectile dysfunction. J Sex Med 2010; 7:445-75. [PMID: 20092448 DOI: 10.1111/j.1743-6109.2009.01624.x] [Citation(s) in RCA: 231] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
INTRODUCTION Significant scientific advances during the past 3 decades have deepened our understanding of the physiology and pathophysiology of penile erection. A critical evaluation of the current state of knowledge is essential to provide perspective for future research and development of new therapies. AIM To develop an evidence-based, state-of-the-art consensus report on the anatomy, physiology, and pathophysiology of erectile dysfunction (ED). METHODS Consensus process over a period of 16 months, representing the opinions of 12 experts from seven countries. MAIN OUTCOME MEASURE Expert opinion was based on the grading of scientific and evidence-based medical literature, internal committee discussion, public presentation, and debate. RESULTS ED occurs from multifaceted, complex mechanisms that can involve disruptions in neural, vascular, and hormonal signaling. Research on central neural regulation of penile erection is progressing rapidly with the identification of key neurotransmitters and the association of neural structures with both spinal and supraspinal pathways that regulate sexual function. In parallel to advances in cardiovascular physiology, the most extensive efforts in the physiology of penile erection have focused on elucidating mechanisms that regulate the functions of the endothelium and vascular smooth muscle of the corpus cavernosum. Major health concerns such as atherosclerosis, hyperlipidemia, hypertension, diabetes, and metabolic syndrome (MetS) have become well integrated into the investigation of ED. CONCLUSIONS Despite the efficacy of current therapies, they remain insufficient to address growing patient populations, such as those with diabetes and MetS. In addition, increasing awareness of the adverse side effects of commonly prescribed medications on sexual function provides a rationale for developing new treatment strategies that minimize the likelihood of causing sexual dysfunction. Many basic questions with regard to erectile function remain unanswered and further laboratory and clinical studies are necessary.
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Affiliation(s)
- Christian Gratzke
- Department of Urology, Ludwig-Maximilians-Universität, München, Germany
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Seo Y, Jeong B, Kim JW, Choi J. Plasma concentration of prolactin, testosterone might be associated with brain response to visual erotic stimuli in healthy heterosexual males. Psychiatry Investig 2009; 6:194-203. [PMID: 20046395 PMCID: PMC2799222 DOI: 10.4306/pi.2009.6.3.194] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2009] [Revised: 07/05/2009] [Accepted: 07/08/2009] [Indexed: 01/23/2023] Open
Abstract
OBJECTIVE Many studies have showed that excess or lack of sexual hormones, such as prolactin and testosterone, induced the sexual dysfunction in humans. Little, however, is known about the role of sexual hormones showing normal range in, especially, the basal state unexposed to any sexual stimulation. We hypothesized sexual hormones in the basal state may affect sexual behavior. METHODS We investigated the association of the sexual hormones level in the basal hormonal state before visual sexual stimulation with the sexual response-related brain activity during the stimulation. Twelve heterosexual men were recorded the functional MRI signals of their brain activation elicited by passive viewing erotic (ERO), happy-faced (HA) couple, food and nature pictures. Both plasma prolacitn and testosterone concentrations were measured before functional MR scanning. A voxel wise regression analyses were performed to investigate the relationship between the concentration of sexual hormones in basal state and brain activity elicited by ERO minus HA, not food minus nature, contrast. RESULTS The plasma concentration of prolactin in basal state showed positive association with the activity of the brain involving cognitive component of sexual behavior including the left middle frontal gyrus, paracingulate/superior frontal/anterior cingulate gyri, bilateral parietal lobule, right angular, bilateral precuneus and right cerebellum. Testosterone in basal state was positively associated with the brain activity of the bilateral supplementary motor area which related with motivational component of sexual behavior. CONCLUSION Our results suggested sexual hormones in basal state may have their specific target regions or network associated with sexual response.
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Affiliation(s)
- Younghee Seo
- Department of Psychiatry, Eulji University College of Medicine, Daejeon, Korea
| | - Bumseok Jeong
- Department of Psychiatry, Eulji University College of Medicine, Daejeon, Korea
| | - Ji-Woong Kim
- Department of Psychiatry, College of Medical Science, Kongyang University, Daejeon, Korea
| | - Jeewook Choi
- Department of Psychiatry, Daejeon St. Mary's Hospital, The Catholic University of Korea College of Medicine, Daejeon, Korea
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Knegtering H, van den Bosch R, Castelein S, Bruggeman R, Sytema S, van Os J. Are sexual side effects of prolactin-raising antipsychotics reducible to serum prolactin? Psychoneuroendocrinology 2008; 33:711-7. [PMID: 18395353 DOI: 10.1016/j.psyneuen.2008.02.008] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2007] [Revised: 02/17/2008] [Accepted: 02/20/2008] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To assess the degree to which sexual side effects (SSE) are associated with prolactin-raising antipsychotics, and to what degree such SSE are reducible to serum prolactin levels. METHOD A large sample (n=264) of patients treated for 6 weeks with prolactin-raising and prolactin-sparing antipsychotics was assessed for changes in sexual performance in terms of libido, arousal and orgasm using the Antipsychotics and Sexual Functioning Questionnaire. For men also erection and ejaculation were evaluated. At 6 weeks, prolactin levels were assessed and analyzed in relation to sexual performance. RESULTS Men and women reported SSE (libido and orgasm) with about the same frequency. Prolactin-raising medication induced significantly more SSE than prolactin-sparing medication (adjusted OR=3.4, 95% CI: 1.8, 6.5) with 43% of emerging SSE attributable to prolactin-raising medication. When adjusted for serum prolactin, the association between prolactin-raising medication and SSE was reduced but remained significant (OR=2.1, 95% CI: 1.0, 4.5); 27% of emerging SSE remained attributable to prolactin-raising medication. For erectile and ejaculatory dysfunction in men, the attributable fraction due to prolactin-raising medication was 32% before, and 11% after adjustment for serum prolactin. CONCLUSIONS Around 40% of emerging SSE in schizophrenia are attributable to the prolactin-raising properties of antipsychotic medication. Of this attributable fraction, around one-third to two-thirds is directly reducible to the effects of serum prolactin.
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Affiliation(s)
- Henderikus Knegtering
- Department of Psychiatry, University Medical Center Groningen, University of Groningen, Hanzeplein 1, PO Box 30.001, 9700 RB Groningen, The Netherlands.
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15
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Breigeiron MK, Lucion AB, Sanvitto GL. Effects of renovascular hypertension on reproductive function in male rats. Life Sci 2007; 80:1627-34. [PMID: 17316702 DOI: 10.1016/j.lfs.2007.01.030] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2006] [Revised: 12/22/2006] [Accepted: 01/20/2007] [Indexed: 01/23/2023]
Abstract
OBJECTIVE The present study investigated the effects of renovascular hypertension (2K/1C model) on the reproductive function of male rats, represented by sexual behavior, plasma prolactin (PRL), luteinizing hormone (LH), follicle-stimulating hormone (FSH) and testosterone, and spermatogenesis. METHODS The present experiments were performed to investigate the reproductive function of 2K/1C male Wistar rats and compare with 2K/1C male rats successfully treated for hypertension with nifedipine and was divided in the following groups: (1) Sham+V (n=10): Sham-operated males with vehicle used; (2) Sham+N (n=13): Sham-operated males treated with nifedipine (10 mg/kg/day); (3) 2K/1C+V (n=14): 2K/1C-operated males with vehicle used; and (4) 2K/1C+N (n=16): 2K/1C-operated males treated with nifedipine. RESULTS The data indicated an association between hypertension induced by the 2K/1C model and reduction of reproductive function, as demonstrated by an impairment of sexual behavior, higher plasma PRL and lower plasma testosterone and FSH. The treatment with nifedipine prevented the reduction of sexual behavior and the increase of plasma PRL, but did not alter the reduction of plasma testosterone and FSH and spermatogenesis of 2K/1C rats. CONCLUSIONS Reproductive function is adversely affected in the 2K/1C animal model, and high blood pressure plays a role in the modulation of plasma PRL and sexual behavior. Moreover, other events, without high blood pressure, but with high plasma renin activity associated with the 2K/1C model, contribute directly to the reduction of plasma testosterone and FSH and impaired spermatogenesis.
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MESH Headings
- Animals
- Disease Models, Animal
- Female
- Follicle Stimulating Hormone/blood
- Hypertension, Renovascular/complications
- Hypertension, Renovascular/drug therapy
- Hypertension, Renovascular/physiopathology
- Infertility, Male/blood
- Infertility, Male/drug therapy
- Infertility, Male/etiology
- Infertility, Male/physiopathology
- Luteinizing Hormone/blood
- Male
- Nifedipine/therapeutic use
- Prolactin/blood
- Rats
- Rats, Wistar
- Reproduction/drug effects
- Reproduction/physiology
- Sexual Behavior, Animal/drug effects
- Sexual Behavior, Animal/physiology
- Spermatogenesis/drug effects
- Spermatogenesis/physiology
- Testosterone/blood
- Vasodilator Agents/therapeutic use
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Affiliation(s)
- Márcia Koja Breigeiron
- Department of Physiology, Institute of Basic Health Sciences, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
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16
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Hernandez ME, Soto-Cid A, Rojas F, Pascual LI, Aranda-Abreu GE, Toledo R, Garcia LI, Quintanar-Stephano A, Manzo J. Prostate response to prolactin in sexually active male rats. Reprod Biol Endocrinol 2006; 4:28. [PMID: 16707016 PMCID: PMC1524775 DOI: 10.1186/1477-7827-4-28] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2006] [Accepted: 05/17/2006] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The prostate is a key gland in the sexual physiology of male mammals. Its sensitivity to steroid hormones is widely known, but its response to prolactin is still poorly known. Previous studies have shown a correlation between sexual behaviour, prolactin release and prostate physiology. Thus, here we used the sexual behaviour of male rats as a model for studying this correlation. Hence, we developed experimental paradigms to determine the influence of prolactin on sexual behaviour and prostate organization of male rats. METHODS In addition to sexual behaviour recordings, we developed the ELISA procedure to quantify the serum level of prolactin, and the hematoxilin-eosin technique for analysis of the histological organization of the prostate. Also, different experimental manipulations were carried out; they included pituitary grafts, and haloperidol and ovine prolactin treatments. Data were analyzed with a One way ANOVA followed by post hoc Dunnet test if required. RESULTS Data showed that male prolactin has a basal level with two peaks at the light-dark-light transitions. Consecutive ejaculations increased serum prolactin after the first ejaculation, which reached the highest level after the second, and started to decrease after the third ejaculation. These normal levels of prolactin did not induce any change at the prostate tissue. However, treatments for constant elevations of serum prolactin decreased sexual potency and increased the weight of the gland, the alveoli area and the epithelial cell height. Treatments for transient elevation of serum prolactin did not affect the sexual behaviour of males, but triggered these significant effects mainly at the ventral prostate. CONCLUSION The prostate is a sexual gland that responds to prolactin. Mating-induced prolactin release is required during sexual encounters to activate the epithelial cells in the gland. Here we saw a precise mechanism controlling the release of prolactin during ejaculations that avoid the detrimental effects produced by constant levels. However, we showed that minor elevations of prolactin which do not affect the sexual behaviour of males, produced significant changes at the prostate epithelium that could account for triggering the development of hyperplasia or cancer. Thus, it is suggested that minute elevations of serum prolactin in healthy subjects are at the etiology of prostate abnormal growth.
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Affiliation(s)
- Maria Elena Hernandez
- Instituto de Neuroetologia, Universidad Veracruzana, AP 566, Xalapa, Ver., 91000, Mexico
| | - Abraham Soto-Cid
- Facultad de Quimica Farmaceutica Biologica, Universidad Veracruzana, Xalapa, Ver., 91000, Mexico
| | - Fausto Rojas
- Instituto de Neuroetologia, Universidad Veracruzana, AP 566, Xalapa, Ver., 91000, Mexico
| | - Luz I Pascual
- Instituto de Neuroetologia, Universidad Veracruzana, AP 566, Xalapa, Ver., 91000, Mexico
| | - Gonzalo E Aranda-Abreu
- Instituto de Neuroetologia, Universidad Veracruzana, AP 566, Xalapa, Ver., 91000, Mexico
| | - Rebeca Toledo
- Instituto de Neuroetologia, Universidad Veracruzana, AP 566, Xalapa, Ver., 91000, Mexico
| | - Luis I Garcia
- Instituto de Neuroetologia, Universidad Veracruzana, AP 566, Xalapa, Ver., 91000, Mexico
| | - Andres Quintanar-Stephano
- Centro de Ciencias Basicas, Universidad Autonoma de Aguascalientes, Aguascalientes, Ags., 20100, Mexico
| | - Jorge Manzo
- Instituto de Neuroetologia, Universidad Veracruzana, AP 566, Xalapa, Ver., 91000, Mexico
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17
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Krüger THC, Hartmann U, Schedlowski M. Prolactinergic and dopaminergic mechanisms underlying sexual arousal and orgasm in humans. World J Urol 2005; 23:130-8. [PMID: 15889301 DOI: 10.1007/s00345-004-0496-7] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2004] [Accepted: 12/08/2004] [Indexed: 12/16/2022] Open
Abstract
Dopaminergic mechanisms play a major role in modulating sexual behavior in humans and animals. Animal data demonstrate important interactions between the dopaminergic and prolactinergic system. As recently demonstrated, dopamine agonists have facilitatory properties for penile erection but may also enhance sexual drive and orgasmic quality. In contrast, chronic elevations of prolactin inhibit appetitive as well as consummatory parameters of sexual behavior. Recent human studies show a marked increase in prolactin after orgasm in males and females. Concerning the biological relevance of acute prolactin alterations after orgasm, prolactin might serve as a neuroendocrine reproductive reflex for peripheral reproductive organs. Alternatively, prolactin may feedback to dopaminergic neurons in the central nervous system and thereby modulate sexual drive and satiation. Here, we provide a brief overview of the physiology of dopamine and prolactin in regulating sexual behavior. In addition, recent experimental and clinical evidence for a postulated feedback mechanism for prolactin and its implications for orgasmic disorders are discussed.
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Affiliation(s)
- Tillmann H C Krüger
- Department of Clinical Psychiatry and Psychotherapy, Medical School Hannover, Carl-Neuberg-Strasse 1, 30625 Hanover, Germany.
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18
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Codispoti M, Gerra G, Montebarocci O, Zaimovic A, Raggi MA, Baldaro B. Emotional perception and neuroendocrine changes. Psychophysiology 2004; 40:863-8. [PMID: 14986839 DOI: 10.1111/1469-8986.00104] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The present study was designed to investigate the neuroendocrine modifications during affective states. In particular, we investigate if the pleasantness of the stimuli has a different effect on neuroendocrine responses. To address this issue, we compared the effects of pleasant, neutral, and unpleasant pictures on catecholamine, adrenocorticotrophic hormone (ACTH), cortisol, and prolactin plasma levels. Ten male participants were submitted to three experimental sessions, each on one of the three experimental days, a week apart in a counterbalanced order. Although in the subjective arousal rating, pleasant (erotic pictures) and unpleasant stimuli (pictures of mutilated bodies) receive the same high score, a different neuroendocrine pattern was obtained: unpleasant stimuli elicited a decrease in prolactin concentration and increases in noradrenaline, cortisol, and ACTH levels, whereas pleasant slide set viewing induced an increase in prolactin levels. The results suggest that the neuroendocrine system responds selectively to affective motivationally relevant pictures.
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19
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Sider LH, Hucke EETS, Florio JC, Felicio LF. Influence of time of day on hypothalamic monoaminergic activity in early pregnancy: effect of a previous reproductive experience. Psychoneuroendocrinology 2003; 28:195-206. [PMID: 12510012 DOI: 10.1016/s0306-4530(02)00016-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Several dopamine-related neurochemical and behavioral responses are influenced by the time of day. The light-dark shift is a major zeitgeber for various functionally important hypothalamic monoaminergic systems. However, these influences are modulated by reproductive state and by reproductive experience (RE) in females. Early pregnancy in rodents generates diurnal and nocturnal prolactin surges that are reduced in intensity in a second pregnancy. Dopamine (DA) is a major inhibitory factor of prolactin synthesis and secretion. Other neurotransmitters such as serotonin (5HT) and norepinephrine (NE) can modulate prolactin secretion as well. Previous works have demonstrated that RE induces changes in central concentrations of both dopamine and serotonin. In addition, RE modulates the responses of both dopaminergic and serotoninergic nerve terminals. The present investigation was designed to examine the possible effects of RE on hypothalamic concentrations of DA, NE, 5HT and their major metabolites homovanillic acid (HVA), 3-4-dihydroxyphenyl acetic acid (DOPAC), 3-methoxy mandelic acid (VMA) and 5-hydroxyindole 3-acetic acid (5HIAA), respectively. These parameters were measured in pregnant rats during the light-dark shift and the prolactin surges. Primi- and multigravid rats were sacrificed on the 7th-8th day of pregnancy between 1700 and 1900 h (light-dark shift and diurnal prolactin surge) or 0200 and 0400 h (nocturnal prolactin surge), and hypothalamic concentrations of DA, NE and 5HT and their metabolites were measured by high performance liquid chromatography coupled to an electrochemical detector (HPLC-ED). Trunk blood was collected and serum prolactin measured by radioimmunoassay. The prolactin surge was confirmed and multigravid rats showed significantly lower serum prolactin levels as compared to primigravid rats between 0200 and 0400 h. During the light-dark shift DA and NE concentrations increased while DOPAC/DA, HVA/DA and 5HIAA/5HT ratios decreased in multigravid rats compared to primigravid rats. Except for 5HIAA/5HT, these differences were not observed during the prolactin nocturnal surge. These results suggest that a previous reproductive experience induces central functional changes during pregnancy which are expressed differently according to the time of day.
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Affiliation(s)
- Lucia H Sider
- Departamento de Patologia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Cidade Universitária, Brazil
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20
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Teodorov E, Salzgeber SA, Felicio LF, Varolli FMF, Bernardi MM. Effects of perinatal picrotoxin and sexual experience on heterosexual and homosexual behavior in male rats. Neurotoxicol Teratol 2002; 24:235-45. [PMID: 11943511 DOI: 10.1016/s0892-0362(01)00213-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The effects of perinatal picrotoxin (0.75 mg/kg) on heterosexual and homosexual behavior of male rats, sexually experienced or not, were studied. The following data were obtained: (1) at birth, body weight and anogenital distance were not modified by the treatment; (2) during lactation, both treatment and sex interfered with body weight as well as in adult age; (3) as experimental animals were trained, the heterosexual behavior was improved; (4) picrotoxin treatment reduced lordotic response of homosexual behavior in inexperienced male rats and (5) the heterosexual experience with female rats inhibited homosexual behavior of both experimental and control animals. These results suggest that perinatal maternal picrotoxin exposure improved heterosexual behavior in male rats and the sexual experience reveals this effect. In addition, picrotoxin did not induce feminization in experimental inexperienced rats. Finally, the sexual experience per se promotes changes in brain regions related to male behavioral and sexual aspects.
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Affiliation(s)
- Elizabeth Teodorov
- Department of Pathology, Faculty of Veterinary Medicine and Zootechny, University of São Paulo, Brazil
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21
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Beinfeld MC, Bittencourt JC, Bridges RS, Faris PL, Lucion AB, Nasello AG, Weller A, Felicio LF. The brain decade in debate: VIII. Peptide hormones and behavior: cholecystokinin and prolactin. Braz J Med Biol Res 2001; 34:1369-77. [PMID: 11668345 DOI: 10.1590/s0100-879x2001001100002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
This article is a transcription of an electronic symposium held on November 28, 2000 in which active researchers were invited by the Brazilian Society of Neuroscience and Behavior (SBNeC) to discuss the advances of the last decade in the peptide field with particular focus on central actions of prolactin and cholecystokinin. The comments in this symposium reflect the diversity of prolactin and cholecystokinin research and demonstrate how the field has matured. Since both peptides play a role in reproductive behaviors, particularly mother-infant interactions, this was the starting point of the discussion. Recent findings on the role of the receptor subtypes as well as interaction with other peptides in this context were also discussed. Another issue discussed was the possible role of these peptides in dopamine-mediated rewarding systems. Both prolactin and cholecystokinin are involved in mechanisms controlling food intake and somatic pain thresholds. The role of peripheral inputs through vagal afferents modulating behavior was stressed. The advent of knockout animals as potential generators of new knowledge in this field was also addressed. Finally, interactions with other neuropeptides and investigation of the role of these peptides in other fields such as immunology were mentioned. Knowledge about the central functions of prolactin and cholecystokinin has shown important advances. The role of these peptides in neurological and psychiatric syndromes such as anorexia, drug abuse and physiological disturbances that lead to a compromised maternal behavior seems relevant.
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Affiliation(s)
- M C Beinfeld
- Department of Pharmacology and Experimental Therapeutics, Tufts University School of Medicine, Boston, MA, USA
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22
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Lafuente A, Fenández-Rey E, Seara R, Pérez-Lorenzo M, Esquifino AI. Alternate cadmium exposure differentially affects amino acid metabolism within the hypothalamus, median eminence, striatum and prefrontal cortex of male rats. Neurochem Int 2001; 39:187-92. [PMID: 11434976 DOI: 10.1016/s0197-0186(01)00029-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This work was designed to analyze the possible changes in glutamate, aspartate and glutamine content induced by cadmium exposure in the hypothalamus, striatum and prefrontal cortex of rats, using an alternate schedule of metal administration. Pubertal-adult differences were also evaluated. In adult control rats, glutamate and aspartate contents in the anterior hypothalamus decreased as compared to pubertal controls. After cadmium administration from day 30 to 60 of life, the content of anterior hypothalamic glutamate and aspartate diminished. In adult control animals, the glutamine content increased in mediobasal hypothalamus as compared to pubertal controls. After cadmium exposure from day 30 to 60 of life, the mediobasal glutamine content increased, and after cadmium treatment from day 60 to 90 of life, the mediobasal aspartate content decreased. In adult control rats the content of glutamine, glutamate and aspartate of the posterior hypothalamus decreased significantly. After cadmium administration in pubertal animals, posterior hypothalamic contents of glutamine, glutamate and aspartate diminished. Cadmium treatment of adult animals caused a decrease in glutamine content, as compared to controls. In adult control rats, only glutamate and aspartate content increased in the prefrontal cortex as compared to the values found in pubertal controls. When cadmium was administered to adult animals, only the aspartate content decreased. In the striatum, cadmium decreased the glutamine and aspartate contents when administered from day 60 to 90 of life. These data suggest that cadmium differentially affects amino acid metabolism in the hypothalamus, striatum and prefrontal cortex. Age-dependent effects of cadmium on these brain areas appeared to have occurred.
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Affiliation(s)
- A Lafuente
- Laboratorio de Toxicología, Facultad de Ciencias, Universidad de Vigo, Campus de Orense, Las Lagunas, 32004-Orense, Spain.
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23
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Exton MS, Krüger TH, Koch M, Paulson E, Knapp W, Hartmann U, Schedlowski M. Coitus-induced orgasm stimulates prolactin secretion in healthy subjects. Psychoneuroendocrinology 2001; 26:287-94. [PMID: 11166491 DOI: 10.1016/s0306-4530(00)00053-6] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Previous data have indicated that orgasm produces marked alterations in plasma prolactin concentrations in men and women. Thus, the current study aimed to extend these data by examining prolactin response to coitus in healthy males and females. Ten pairs of healthy heterosexual couples participated in the study. Blood was drawn continuously for 20 min before, during, and until 60 min following sexual intercourse and orgasm. Plasma was subsequently analysed for prolactin concentrations. Coitus-induced orgasm produced a marked elevation of plasma prolactin in both males and females. Plasma prolactin concentrations remained elevated 1 h following orgasm. These data, together with previous evidence that masturbation-induced orgasm produces pronounced, long-lasting increases in plasma prolactin concentrations in both males and females, suggest a role for acute prolactin alterations in modifying human sexual desire following orgasm.
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Affiliation(s)
- M S Exton
- Institute of Medical Psychology, University of Essen, Hufelandstrasse 55, 45122, Essen, Germany.
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24
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Silva MR, Bernardi MM, Felicio LF. Effects of dopamine receptor antagonists on ongoing maternal behavior in rats. Pharmacol Biochem Behav 2001; 68:461-8. [PMID: 11325400 DOI: 10.1016/s0091-3057(01)00471-3] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The effects of different peripheral doses of four dopamine (DA) receptor antagonists on general activity and maternal behavior were examined in lactating female rats. Administration of the classic D1-like and D2-like DA receptor blocker haloperidol (0.1 and 0.05 mg/kg) disrupted pup retrieval and nest-building behaviors and reduced motor activity. Pimozide (0.5 and 0.2 mg/kg), which has more affinity for DA D2-like receptors, mildly disrupted pup retrieval while showing no significant influence on open-field behaviors. The putative DA D(4) receptor blocker, clozapine (1.5 and 1.0 mg/kg) reduced motor activity significantly, while only 1.0 mg/kg dose significantly decreased percent of rats displaying nest building. The DA D1-like receptor blocker SKF-83566 (0.2 and 0.1 mg/kg) significantly reduced pup retrieval, nest building and motor activity. These results suggest a role for DA receptors in ongoing maternal behavior that correlates directly with general activity.
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Affiliation(s)
- M R Silva
- Departamento de Farmacologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
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25
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Drago F, Lissandrello CO. The "low-dose" concept and the paradoxical effects of prolactin on grooming and sexual behavior. Eur J Pharmacol 2000; 405:131-7. [PMID: 11033320 DOI: 10.1016/s0014-2999(00)00678-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The effects of prolactin on animal behavior include the stimulation of novelty-induced grooming in rats. This effect has been demonstrated in hyperprolactinaemic animals bearing pituitary homografts under the kidney capsule or after intracerebroventricular (i.c.v.) administration of prolactin. Since plasma prolactin levels in hyperprolactinaemic rats are similar to those of animals injected with low doses of rat prolactin, we studied the effects of this hormone injected subcutaneously (s.c.) in a dose range of 5-50 microg/kg. Novelty-induced grooming was enhanced only in rats injected with 5 or 10 microg/kg rat prolactin, whereas no effect was observed after the s.c. injection of the higher dose. The sexual behavior of male rats is also affected by prolactin. Male rats with normal mating activity showed enhanced sexual behavior when injected s.c. with rat prolactin (5, 10 or 50 microg/kg). In animals with poor sexual performance or in impotent rats, prolactin (5 or 10 microg/kg, but not 50 microg/kg) restored the full pattern of sexual behavior. An increased lordosis quotient was also observed in ovariectomized rats treated with prolactin 5 or 10 microg/kg. These results suggest that, besides the duration of hyperprolactinaemia, the effective level of plasma prolactin is important for the expression of the behavioral effects of this hormone.
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Affiliation(s)
- F Drago
- Department of Experimental and Clinical Pharmacology, Institute of Pharmacology, Faculty of Medicine, University of Catania Medical School, Catania, Italy.
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