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Ijiro T, Yaguchi A, Yokoyama A, Kiguchi S. Rovatirelin ameliorates motor dysfunction in the cytosine arabinoside‐induced rat model of spinocerebellar degeneration via acetylcholine and dopamine neurotransmission. Clin Exp Pharmacol Physiol 2022; 49:950-958. [DOI: 10.1111/1440-1681.13675] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 01/04/2022] [Accepted: 05/25/2022] [Indexed: 12/01/2022]
Affiliation(s)
- Tomoyuki Ijiro
- Central Research Laboratories, Kissei Pharmaceutical Co, Ltd. Nagano Japan
| | - Atsushi Yaguchi
- Central Research Laboratories, Kissei Pharmaceutical Co, Ltd. Nagano Japan
| | - Ayaka Yokoyama
- Central Research Laboratories, Kissei Pharmaceutical Co, Ltd. Nagano Japan
| | - Sumiyoshi Kiguchi
- Central Research Laboratories, Kissei Pharmaceutical Co, Ltd. Nagano Japan
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Zhao S, Xia Y, Huang Y, Zou H, Wang X, Chen Z, Zhou H, Han Y, Tang H, Yan R, Yao Z, Lu Q. The Correlation Between Thyroid Function, Frontal Gray Matter, and Executive Function in Patients With Major Depressive Disorder. Front Endocrinol (Lausanne) 2021; 12:779693. [PMID: 34887837 PMCID: PMC8649711 DOI: 10.3389/fendo.2021.779693] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Accepted: 11/03/2021] [Indexed: 11/13/2022] Open
Abstract
The present study was aimed to investigate the relationships between serum thyroid hormones (THs), frontal gray matter volume, and executive function in selected patients with major depressive disorder (MDD). One hundred and four MDD patients and seventy-five healthy controls (HCs) were subjected to thyroid-stimulating hormone (TSH), free Triiodothyronine (fT3), free Thyroxine (fT4), and executive function tests and underwent structural magnetic resonance imaging (MRI). Voxel-based morphometry (VBM) analysis was performed to compare group differences in the gray matter for the frontal lobe. Furthermore, mediation analysis was used to investigate whether gray matter volumes of the frontal gyrus mediated the relationship between serum THs and executive function in MDD patients. MDD patients exhibited significant gray matter volume reduction in several brain regions, including the left rectus, right middle frontal cortex, and left middle frontal cortex. Serum TSH levels are positively associated with altered regional gray matter volume patterns within MFG and executive function. Importantly, gray matter in the right MFG was a significant mediator between serum TSH levels and executive function. These findings expand our understanding of how thyroid function affects brain structure changes and executive function in MDD patients.
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Affiliation(s)
- Shuai Zhao
- Department of Psychiatry, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing, China
| | - Yi Xia
- Department of Psychiatry, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing, China
| | - Yinghong Huang
- Nanjing Brain Hospital, Medical School of Nanjing University, Nanjing, China
| | - Haowen Zou
- Nanjing Brain Hospital, Medical School of Nanjing University, Nanjing, China
| | - Xumiao Wang
- Department of Psychiatry, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing, China
| | - Zhilu Chen
- Department of Psychiatry, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing, China
| | - Hongliang Zhou
- Department of Psychiatry, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing, China
| | - Yinglin Han
- Department of Psychiatry, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing, China
| | - Hao Tang
- Department of Psychiatry, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing, China
| | - Rui Yan
- Department of Psychiatry, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing, China
| | - Zhijian Yao
- Department of Psychiatry, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing, China
- Nanjing Brain Hospital, Medical School of Nanjing University, Nanjing, China
- *Correspondence: Zhijian Yao, ; Qing Lu,
| | - Qing Lu
- School of Biological Sciences & Medical Engineering, Southeast University, Nanjing, China
- Child Development and Learning Science, Key Laboratory of Ministry of Education, Nanjing, China
- *Correspondence: Zhijian Yao, ; Qing Lu,
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Szlejf C, Suemoto CK, Santos IS, Lotufo PA, Haueisen Sander Diniz MDF, Barreto SM, Benseñor IM. Thyrotropin level and cognitive performance: Baseline results from the ELSA-Brasil Study. Psychoneuroendocrinology 2018; 87:152-158. [PMID: 29096222 DOI: 10.1016/j.psyneuen.2017.10.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 10/18/2017] [Accepted: 10/20/2017] [Indexed: 11/19/2022]
Abstract
BACKGROUND AND AIMS The role of subtle thyroid alterations, such as subclinical thyroid disease and low/high serum thyrotropin (TSH) within the normal range, on cognitive decline is controversial. The aim of this study was to evaluate the association of serum TSH and subclinical thyroid dysfunction with performance on cognitive tests in a large sample of Brazilian middle-aged adults without overt thyroid disease. METHODS In this cross-sectional analysis of the Brazilian Longitudinal Study of Adult Health, we excluded individuals aged 65 years and older, with overt thyroid dysfunction, prevalent stroke, in use of medications that affect thyroid function or that indicate neurologic diseases, and from Asian or indigenous ethnicity. Thyroid status was assessed by serum TSH and free thyroxine (only when the TSH was altered). Individuals were divided according to TSH tertiles and classified according to thyroid function as euthyroidism, subclinical hypothyroidism, or subclinical hyperthyroidism. Cognition was evaluated using delayed word recall test, semantic verbal fluency test, and trail making test version B. The associations of cognitive tests performance with TSH tertiles (using the middle tertile as reference) and thyroid function were investigated using linear regression models, adjusted for an extensive set of possible confounders (sociodemographic characteristics, cardiovascular risk factors, and depression). RESULTS The mean age of the 10,362 participants was 49.5±7.4years, 52.3% women. After adjustment for confounders, the first TSH tertile was associate with worse performance on the trail making test (β=-0.05, 95% CI=-0.09; -0.01, p=0.017). When restricting the analysis to the 9769 individuals with TSH within the normal range, the association between TSH and performance on the trail making test remained significant (β=-0.05, 95% CI=-0.09; -0.01, p=0.020) on multiple linear regression. Subclinical thyroid disease was not associated with performance on cognitive tests. CONCLUSION Low TSH is associated with poorer performance on an executive function test in middle-aged adults without overt thyroid dysfunction.
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Affiliation(s)
- Claudia Szlejf
- Center for clinical and epidemiological research, Hospital Universitario, University of Sao Paulo, Sao Paulo, Brazil; Instituto Nacional de Geriatría, Mexico City, Mexico.
| | - Claudia K Suemoto
- Division of Geriatrics, University of Sao Paulo Medical School, Sao Paulo, Brazil; Department of Global Health and Population, Harvard School of Public Health, Boston, USA
| | - Itamar S Santos
- Center for clinical and epidemiological research, Hospital Universitario, University of Sao Paulo, Sao Paulo, Brazil; Department of Internal Medicine, University of Sao Paulo Medical School, Sao Paulo, Brazil
| | - Paulo A Lotufo
- Center for clinical and epidemiological research, Hospital Universitario, University of Sao Paulo, Sao Paulo, Brazil; Department of Internal Medicine, University of Sao Paulo Medical School, Sao Paulo, Brazil
| | | | | | - Isabela M Benseñor
- Center for clinical and epidemiological research, Hospital Universitario, University of Sao Paulo, Sao Paulo, Brazil; Department of Internal Medicine, University of Sao Paulo Medical School, Sao Paulo, Brazil
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Asai H, Watanabe Y, Yamauchi-Kohno R, Doi O. Reversal of hemorrhagic shock in rats using the metabolically stable thyrotropin-releasing hormone analog taltirelin hydrate. J Recept Signal Transduct Res 2011; 31:416-22. [DOI: 10.3109/10799893.2011.625427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Ceresini G, Ceda GP, Lauretani F, Maggio M, Bandinelli S, Guralnik JM, Cappola AR, Usberti E, Morganti S, Valenti G, Ferrucci L. Mild thyroid hormone excess is associated with a decreased physical function in elderly men. Aging Male 2011; 14:213-9. [PMID: 21875391 PMCID: PMC4588067 DOI: 10.3109/13685538.2011.606514] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
INTRODUCTION In the adult, subclinical hyperthyroidism (Shyper) may alter skeletal muscle mass and strength. However, whether these effects are present in elderly subjects is not known. We explored the relationship between mild hyperthyroidism and physical function in a population-based sample of older persons. METHODS In a cross-sectional analysis, calf muscle cross-sectional area (CMA), handgrip strength, nerve conduction velocity (NCV), and Short Physical Performance Battery (SPPB) scores were compared between 364 euthyroid (Eut) and 28 Shyper men as well as between 502 Eut and 39 Shyper women. In a longitudinal analysis, we evaluated the relationship between baseline plasma TSH, FT3 and FT4 and the 3-year change in SPPB score in 304 men and 409 women who were euthyroid at enrolment. RESULTS At the cross-sectional analysis, Shyper men, but not women, had a significantly (p = 0.02) lower SPPB score than Eut controls, although with comparable CMA, grip strength and NCV, and were more likely to have poor physical performance (odds ratio = 2.97, p < 0.05). Longitudinal analysis showed that in Eut men higher baseline FT4 was significantly (p = 0.02) predictive of a lower SPPB score at the 3-year follow-up. CONCLUSION Even a modest thyroid hormone excess is associated with a reduced physical function in elderly men.
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Affiliation(s)
- Graziano Ceresini
- Department of Internal Medicine and Biomedical Sciences, Section of Geriatrics-Endocrine Unit, University of Parma, Parma, Italy.
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Ceresini G, Lauretani F, Maggio M, Ceda GP, Morganti S, Usberti E, Chezzi C, Valcavi R, Bandinelli S, Guralnik JM, Cappola AR, Valenti G, Ferrucci L. Thyroid function abnormalities and cognitive impairment in elderly people: results of the Invecchiare in Chianti study. J Am Geriatr Soc 2009; 57:89-93. [PMID: 19054181 PMCID: PMC2631617 DOI: 10.1111/j.1532-5415.2008.02080.x] [Citation(s) in RCA: 122] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
OBJECTIVES To investigate thyroid function testing abnormalities in older persons and to explore the relationship between thyroid dysfunction and cognition. DESIGN Cross-sectional. SETTING Community-based. PARTICIPANTS One thousand one hundred seventy-one men and women aged 23 to 102. MEASUREMENTS Thyroid function was evaluated by measuring plasma concentrations of thyrotropin (TSH), free thyroxine (FT4), and free triiodothyronine (FT3). Cognition was evaluated using the Mini-Mental State Examination (MMSE). Prevalence of overt and subclinical thyroid dysfunction was evaluated in different age groups (<65 vs > or =65). Age trends in TSH, FT4, and FT3 were examined in euthyroid participants. The cross-sectional association between thyroid dysfunction and MMSE score was evaluated adjusting for confounders. RESULTS Subclinical hypothyroidism and subclinical hyperthyroidism were more prevalent in older than in younger participants (subclinical hypothyroidism, 3.5% vs 0.4%, P<.03; subclinical hyperthyroidism, 7.8% vs 1.9%, P<.002). In euthyroid participants, TSH and FT3 declined with age, whereas FT4 increased. Older participants with subclinical hyperthyroidism had lower MMSE scores than euthyroid subjects (22.61+/-6.88 vs 24.72+/-4.52, P<.03). In adjusted analyses, participants with subclinical hyperthyroidism were significantly more likely to have cognitive dysfunction (hazard rate=2.26, P=.003). CONCLUSION Subtle age-related changes in FT3, FT4, and TSH occur in individuals who remain euthyroid. Subclinical hyperthyroidism is the most prevalent thyroid dysfunction in Italian older persons and is associated with cognitive impairment.
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Affiliation(s)
- Graziano Ceresini
- Department of Geriatrics, Endocrine Unit, University of Parma, Italy.
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Kinoshita K, Yamamura M, Sugihara J, Suzuki M, Matsuoka Y. Taltirelin Hydrate (TA-0910): An Orally Active Thyrotropin-Releasing Hormone Mimetic Agent with Multiple Actions. CNS DRUG REVIEWS 2006. [DOI: 10.1111/j.1527-3458.1998.tb00039.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Nakamura T, Honda M, Kimura S, Tanabe M, Oda SI, Ono H. Taltirelin improves motor ataxia independently of monoamine levels in rolling mouse nagoya, a model of spinocerebellar atrophy. Biol Pharm Bull 2006; 28:2244-7. [PMID: 16327158 DOI: 10.1248/bpb.28.2244] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To examine the relationship between motor ataxia and monoamine levels in the central nervous system, the contents and concentrations of noradrenaline (NA), dopamine (DA) and serotonin (5-HT) in the cerebellum, brain stem and spinal cord were measured in rolling mouse Nagoya (RMN), a murine model of spinocerebellar atrophy. The tissue weight of the cerebellum and spinal cord, but not that of the brain stem was significantly lower in RMN than in the control group. In RMN, the NA content of the brain stem and spinal cord, but not the cerebellum were decreased relative to the control, and the concentration of NA in the spinal cord was also lower, but not significant. The DA and 5-HT contents in each tissue did not differ from those of the control, but the concentrations of monoamines, except for DA, were elevated in the brain stem and spinal cord in RMN. In particular, the concentrations of NA, DA and 5-HT in the cerebellum were significantly increased in RMN. Repeated administration of tartilerin hydrate, an analog of thyrotropin-releasing hormone, improved the ataxia of RMN, and elicited no obvious changes in either monoamine content or concentration of cerebellum, brain stem and spinal cord. These results indicate that the concentration of DA, as well as NA and 5-HT, increased in the RMN cerebellum, and that tartilerin improves the motor function of these mice via mechanisms other than changes in the levels of NA, DA and 5-HT in the central nervous system.
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Affiliation(s)
- Tomoka Nakamura
- Laboratory of CNS Pharmacology, Graduate School of Pharmaceutical Sciences, Nagoya City University, Japan
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Urayama A, Yamada S, Ohmori Y, Deguchi Y, Uchida S, Kimura R. Blood-brain permeability of [3H]-(3-methyl-His2)thyrotropin-releasing hormone (MeTRH) in mice: effects of TRH and its analogues. Drug Metab Pharmacokinet 2005; 18:310-8. [PMID: 15618750 DOI: 10.2133/dmpk.18.310] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The present study was undertaken to characterize the transport of (3-methyl-His(2)) thyrotropin-releasing hormone ([(3)H]MeTRH) across the blood-brain barrier in mice and the effects of thyrotropin-releasing hormone (TRH) and its analogues (taltirelin and montirelin) on the transport and brain distribution. Integration plot analysis was used to calculate the influx clearance (CL(in)) of [(3)H]MeTRH after intravenous (i.v.) injection in mice. Furthermore, the capillary depletion method was performed to determine whether [(3)H]MeTRH crossed the blood-brain barrier. The effects of TRH and its analogues on the brain distribution of [(3)H]MeTRH were also examined by co-injection with the radioligand. The brain distribution of [(3)H]MeTRH and [(14)C]sucrose increased with the time after i.v. injection in mice, and the level of [(3)H]MeTRH was significantly higher than that of [(14)C]sucrose 5 min after the injection. The CL(in) value of [(3)H]MeTRH was significantly higher than that of [(14)C]sucrose, and the value of [(3)H]MeTRH was reduced by co-injection with unlabeled MeTRH. Also, capillary depletion showed that [(3)H]MeTRH was distributed largely in the brain parenchyma and this distribution was significantly inhibited by co-injection of TRH and montirelin but not taltirelin. The present study indicates that the transport of [(3)H]MeTRH into the brain may be via a saturable process.
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Affiliation(s)
- Akihiko Urayama
- School of Pharmaceutical Sciences and COE21, University of Shizuoka, Japan
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Urayama A, Yamada S, Deguchi Y, Ohmori Y, Kimura R. Studies on the transport of thyrotropin-releasing hormone (TRH) analogues in Caco-2 cell monolayers. J Pharm Pharmacol 2003; 55:603-8. [PMID: 12831502 DOI: 10.1211/002235703765344504] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
The transport mechanisms of thyrotropin-releasing hormone (TRH) and its pharmacologically active analogues ((3-methyl-His(2))TRH (MeTRH), taltirelin, montirelin, azetirelin) across Caco-2 cell monolayers were characterized. The results of kinetic analysis showed a linear relationship between the concentration (over the range 0.5-10 mM) and apical-to-basolateral transport rate of these agents. The permeability coefficients (P(app)) of these agents were not substantially different from each other, and their P(app) ratios of the basolateral-to-apical over the apical-to-basolateral transport were close to one (0.73-1.23). The cellular transport of [(3)H]MeTRH at low concentrations (3-15 nM) showed a linear relationship between the concentration and transport rate. The transport of [(3)H]MeTRH in Caco-2 cell monolayers was neither affected by TRH nor TRH analogues, and there was little difference in P(app) values between [(3)H]MeTRH and [(14)C]mannitol. The cell-per-medium ratio of [(3)H]MeTRH in the cellular uptake experiment was similar to the value of [14C]mannitol. A large excess of TRH and MeTRH did not significantly influence cell-per-medium ratios of [(3)H]MeTRH in Caco-2 cell monolayers. The k'(IAM) value, which represents lipophilicity, was decreased in the following order: montirelin > taltirelin > TRH > azetirelin, and the values varied from 0.234 to 1.028. These results indicate that a paracellular passive diffusion may be the major route for the transport of TRH and its analogues in Caco-2 cell monolayers.
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Affiliation(s)
- Akihiko Urayama
- Department of Biopharmacy, School of Pharmaceutical Sciences and COE21, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan
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Kalmijn S, Mehta KM, Pols HA, Hofman A, Drexhage HA, Breteler MM. Subclinical hyperthyroidism and the risk of dementia. The Rotterdam study. Clin Endocrinol (Oxf) 2000; 53:733-7. [PMID: 11155096 DOI: 10.1046/j.1365-2265.2000.01146.x] [Citation(s) in RCA: 174] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
UNLABELLED AIMS AND SUBJECTS: We investigated the prospective relationship between thyroid status and the risk of dementia and Alzheimer's disease among a random sample of 1843 participants, aged 55 years and over, from the population-based prospective Rotterdam Study. METHODS Thyroid status was measured at baseline (1990-93), through assessment of serum antibodies to thyroid peroxidase (TPO-Abs, positive: >10 IU/ml), serum TSH levels, and when TSH was abnormal (<0.4 or >4.0 mU/l), serum thyroxin levels (T4). At baseline and at follow up, after on average 2 years, participants were screened for dementia. Diagnoses were based on international criteria. RESULTS Persons with reduced TSH levels at baseline had a more than threefold increased risk of dementia (RR = 3.5, 95%CI: 1.2-10.0) and of Alzheimer's disease (RR = 3.5, 95%CI: 1.1-11.5), after adjustment for age and sex. Among persons with reduced TSH levels, T4 levels appeared to be positively related to the risk of dementia (RR per SD increase = 2.9, 95%CI: 0.7-12.2), although none of those who became demented had a T4 level above the normal range (>140 nmol/l). The risk of dementia was especially increased in subjects with low TSH who were positive for TPO-Abs (RR = 23.7, 95%CI: 4.0-140). CONCLUSIONS This is the first prospective study to suggest that subclinical hyperthyroidism in the elderly increases the risk of dementia and Alzheimer's disease.
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Affiliation(s)
- S Kalmijn
- Department of Chronic Diseases Epidemiology, National Institute of Health and the Environment, Bilthoven, The Netherlands
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Tanabe S, Shishido Y, Nakayama Y, Furushiro M, Hashimoto S, Terasaki T, Tsujimoto G, Yokokura T. Effects of arginine-vasopressin fragment 4-9 on rodent cholinergic systems. Pharmacol Biochem Behav 1999; 63:549-53. [PMID: 10462183 DOI: 10.1016/s0091-3057(99)00034-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Arginine-vasopressin fragment 4-9 (AVP4-9) has been demonstrated in animal studies to facilitate learning and memory. To clarify the mechanisms of this facilitation, we focused on the effects of AVP4-9 on rodent cholinergic systems. AVP4-9 (0.1 microM) enhanced the basal and the high-potassium-evoked acetylcholine (ACh) release from rat hippocampal slices (122.4 and 120.0% of control, respectively) in the presence of 1.3 mM calcium (physiological level) at 60 min after the incubation at 37 degrees C. The AVP4-9-stimulated basal ACh release was inhibited by a V1-selective antagonist ([(beta-mercapto-beta,beta-cyclopentamethylene propionic acid)1, O-methyl-Tyr2, Arg8] vasopressin), but not by a V2-selective antagonist ([adamantaneacetyl1, O-ethyl-D-Tyr2, Val4, aminobutyryl6, Arg8,9]-vasopressin). In addition, AVP4-9 did not affect the basal ACh release under the calcium-free condition at 37 degrees C or in the presence of 1.3 mM calcium at 4 degrees C. However, AVP4-9 facilitated the passive-avoidance response of scopolamine (a cholinergic blocker)-induced memory-deficient mice. These findings demonstrate that AVP4-9 stimulates ACh release via mediation by V1-like vasopressin receptors, and shows dependence on calcium ion and temperature. The results also suggest that the mechanism of the facilitative effects of AVP4-9 on learning and memory consist of the observed stimulation of cholinergic systems and other parallel pathways that would not be inhibited by cholinergic blocking.
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Affiliation(s)
- S Tanabe
- Yakult Central Institute for Microbiological Research, Tokyo, Japan
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Abstract
This brief review will discuss the recent literature on several of the central actions of TRH and its analogs. The most prominent of these actions include: (1) the arousal or analeptic effect in drug narcotized animals or in concussion models; (2) the reversal of cognitive deficits produced by various drugs or procedures, and (3) the improvement of several neurological deficits produced in animal models of spinal and/or cerebellar injury. The mediation of these TRH effects by neurotransmitters is discussed. While little has been published on the human neuropsychopharmacology of TRH, and especially of its analogs, the future holds considerable therapeutic promise for these interesting drugs.
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Affiliation(s)
- A Horita
- Department of Pharmacology, University of Washington School of Medicine, Seattle 98195, USA
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