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Krüger S, Cooke RG, Hasey GM, Jorna T, Persad E. Comorbidity of obsessive compulsive disorder in bipolar disorder. J Affect Disord 1995; 34:117-20. [PMID: 7665803 DOI: 10.1016/0165-0327(95)00008-b] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The comorbidity of OCD and bipolar disorder has not been systematically examined. Therefore, we determined the frequency of patients meeting DSM-III criteria for OCD syndrome in a sample of 149 inpatients with DSM-III major affective disorder who had received a clinically reviewed structured diagnostic interview. The frequency of OCD syndrome was not significantly different between subjects with major depression (35.2%, n = 105) and bipolar disorder (35.1%, n = 37). This suggests that OCD is equally common in bipolar as in unipolar patients.
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Cooke RG, Ahmad N. Prostaglandin F2 alpha-induced release of oxytocin from ovine corpora lutea in vitro. PROSTAGLANDINS 1994; 48:257-61. [PMID: 7878193 DOI: 10.1016/0090-6980(94)90012-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Prostaglandin (PG)F2 alpha, in the dose range 1-10(4) nM, failed to elicit oxytocin secretion in vitro from ovine luteal tissue on day 12 of the estrous cycle (estrus = Day 0), during a 60 minute period. Preincubation of luteal slices for 6 hours prior to treatment suggested that tissue desensitization due to the release of endogenous prostaglandins by tissue preparation is not responsible for this lack of response. However, in luteal tissue collected on day 6 of the ovine estrous cycle, PGF2 alpha stimulated oxytocin release in a dose-dependent manner. This apparent change in sensitivity of the ovine corpus luteum in vitro may be due to a combination of a reduction in the luteal oxytocin available for release and saturation of PGF2 alpha receptors in the more mature tissue.
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Abstract
The relationship between Grade II subclinical hypothyroidism and mixed affective states were examined in a cohort of 66 patients with bipolar affective disorder. The overall frequency of Grade II subclinical hypothyroidism was 20%. There was no difference in frequency of subclinical hypothyroidism or in mean thyroid hormone levels between the mixed state and non-mixed-state group.
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Cooke RG, Ahmad N. Potential role for lipoxygenase products of arachidonic acid in prostaglandin F2 alpha-stimulated oxytocin release from the ovine corpus luteum. J Endocrinol 1994; 142:47-52. [PMID: 7964283 DOI: 10.1677/joe.0.1420047] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Intrauterine administration of nordihydroguaiaretic acid (NDGA) will maintain luteal function in sheep and also suppress the release of both oxytocin and prostaglandin F2 alpha (PGF2 alpha) suggesting that 5-lipoxygenase products of arachidonic acid may be involved in ovine luteolysis. During luteolysis, uterine PGF2 alpha is considered to be the major stimulus for the secretion of luteal oxytocin, and we report the effects of 5-lipoxygenase inhibition, via intrauterine NDGA administration, on the ability of PGF2 alpha to effect such secretion. In the NDGA-treated ewes, luteal function was maintained and oestrus delayed, the duration of the oestrous cycle (20 +/- 1 days; mean +/- S.D.; n = 9) being significantly (P < 0.01) longer than in intact controls (15 +/- 1 days, n = 4). Jugular infusions of PGF2 alpha did not stimulate luteal secretion of oxytocin, the effects being comparable with those in ovariectomized ewes. In intact ewes receiving intrauterine infusions of vehicle only, PGF2 alpha produced marked increases in luteal secretion of oxytocin. Also, preinfusion or basal concentrations of oxytocin in this group of ewes (6.6 +/- 1.9 pg/ml) were significantly (P < 0.01) greater than in either the NDGA-treated (3.1 +/- 1.1 pg/ml) or ovariectomized (3.0 +/- 0.6 pg/ml) ewes. The results suggest involvement of 5-lipoxygenase products of arachidonic acid in the release of oxytocin from the ovine corpus luteum.
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Cooke RG, Ahmad N. Suppression of prostaglandin F2 alpha and oxytocin release after inhibition of testosterone synthesis in the goat. Res Vet Sci 1994; 56:95-9. [PMID: 8146461 DOI: 10.1016/0034-5288(94)90202-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Increased peripheral plasma concentrations of testosterone were detected in goats on days 13 and 14 of the oestrous cycle (oestrus = day 0), at the onset of luteolysis. Subcutaneous administration of spironolactone (10 mg kg-1 day-1) on days 10 to 19 inhibited the increases in testosterone, delayed luteolysis and suppressed plasma concentrations of 13,14-dihydro-15-keto-prostaglandin F2 alpha and oxytocin. These results suggest that testosterone of follicular or luteal origin, possibly via aromatisation to oestrogens, is needed to expedite luteolysis and induce oestrus in the goat.
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Payne JH, Nicholson T, Cooke RG. Insensitivity of dispersed caprine luteal cells to β-adrenergic agonists and other putative transmitter substances. Theriogenology 1993; 40:859-63. [PMID: 16727367 DOI: 10.1016/0093-691x(93)90221-p] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/1991] [Accepted: 07/02/1993] [Indexed: 11/19/2022]
Abstract
Adrenaline (10(-6)-10(-4)M), serotonin (10(-6)-10(-4)M), and several other potential steroidogenic agonists failed to enhance either basal or LH-stimulated progesterone production from dispersed caprine luteal cells from Day 10 of the estrous cycle. The caprine corpus luteum (CL) would appear to be more refractory to exogenous stimulation than either the ovine or bovine CL.
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Abstract
Eighty-one outpatients with bipolar disorder (BD) were grouped by SADS anxiety symptom scores (high vs. low) or diagnosis of generalized anxiety disorder, and/or panic disorder. BD patients with high anxiety scores were more likely to have suicidal behaviour (44% vs. 19%), alcohol abuse (28% vs. 6%), cyclothymia (44% vs. 21%) and an anxiety disorder (56% vs. 25%) with a trend toward lithium non-responsiveness. Diagnosis of an anxiety disorder was related only to high anxiety and lower GAS scores. Thus, anxiety may have similar clinical relevance in BD as it does in unipolar patients.
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Payne JH, Cooke RG. Pulsatile release of oxytocin after suppression of prostaglandin synthesis in hysterectomised ewes. Res Vet Sci 1993; 55:38-42. [PMID: 8378611 DOI: 10.1016/0034-5288(93)90031-a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
On days 13 and 14 after oestrus (day 0) oxytocin and 13,14-dihydro-15-keto-prostaglandin (PG)F2 alpha (PGFM) concentrations were measured in jugular plasma of hysterectomised sheep with or without systemic treatment with the PG cyclo-oxygenase inhibitor indomethacin (4 mg kg-1 three times a day on days 12, 13 and 14 subcutaneously. Pulsatile increases of oxytocin were observed in both untreated and treated sheep with mean (+/- SD) peak heights of 18.4 +/- 9.6 pg ml-1 (n = 11) and 23.5 +/- 9.4 pg ml-1 (n = 8), respectively; these means were not significantly different. Plasma concentrations of PGFM remained consistently low in both groups (under 100 pg ml-1) with no significant peaks observed. The data suggest that PGF2 alpha may not be the only stimulus for the release of luteal oxytocin, or that there may be a contribution by the posterior pituitary to oxytocin secretion during the luteal phase of the ovine oestrous cycle.
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Payne J, Cooke RG. Effect of intra-ovarian 6-hydroxydopamine on progesterone secretion in sheep. J Vet Pharmacol Ther 1993; 16:114-6. [PMID: 8478995 DOI: 10.1111/j.1365-2885.1993.tb00298.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Hasey GM, D'Alessandro E, Cooke RG, Warsh JJ. The interface between thyroid activity, magnesium, and depression: a pilot study. Biol Psychiatry 1993; 33:133-5. [PMID: 8439603 DOI: 10.1016/0006-3223(93)90314-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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Arias TD, Barrantes R, Jorge LF, Azofeifa J, Carles M, Cooke RG. ["Cholos de Coclé": determination of their racial mixture and genetic origins]. REVISTA MEDICA DE PANAMA 1992; 17:180-7. [PMID: 1439003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We have found, in this first genetic study of a supposedly admixed Panamanian population, that the cultural group known as "cholos of Coclé" constitute a trihybrid mixture, whose genetic pool has the following composition: 44% Amerindian, 38% Caucasoid and 18% Negroid. Similarly, we have detected Amerindian genes, such as LDHB--Gua and TFchi, in proportions that relate this population with the extant Ngawbé (Guaymí). Nevertheless, the very high frequency of variant PEPA--KUN seems to indicate the genetic contribution of Amerindian populations from Eastern Panama, possibly from the extinct indigenous group cueva. This variant is frequently found among the present-day Kuna, but has not been detected among Nagawbé and Buglé.
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Cooke RG, Payne JH. The effects of adrenaline and atropine on oxytocin-induced estrus in the goat. Theriogenology 1992; 37:761-7. [PMID: 16727077 DOI: 10.1016/0093-691x(92)90039-t] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/1991] [Accepted: 12/12/1991] [Indexed: 10/26/2022]
Abstract
Oxytocin-induced luteolysis in goats was associated with significant increases in peripheral plasma concentrations of 13,14-dihydro-15-keto-prostaglandin (PG) F(2alpha) (PGFM). This effect was not inhibited by concomitant administration of adrenaline (1 mg), although increases of PGFM were both delayed and diminished. Administration of atropine, a muscarinic cholinergic antagonist, inhibited the effect of oxytocin in three out of five goats. In these animals, increases in PGFM were inhibited.
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Cooke RG, Joffe RT, Levitt AJ. T3 augmentation of antidepressant treatment in T4-replaced thyroid patients. J Clin Psychiatry 1992; 53:16-8. [PMID: 1737734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND Clinicians may not consider using the thyroid hormone liothyronine sodium (levorotary isomer of triiodothyronine [T3]) for augmentation of antidepressant drugs in depressed patients who are also receiving the precursor hormone levothyroxine (levorotary isomer of thyroxine [T4]) for thyroid disease. We now report on the successful use of T3 augmentation therapy in seven of nine depressed patients who were also receiving T4 for thyroid disease. METHOD Following an earlier single case report, we prescribed T3 augmentation therapy for eight depressed patients who had not responded to an adequate antidepressant drug trial and who were receiving T4 therapy for thyroid disease. T3 was prescribed in open-label fashion, and response was judged by the clinician, whose assessment was supplemented by the use of standardized rating scales. RESULTS Seven of the nine patients were judged to respond to T3 augmentation. CONCLUSION These results are consistent with a report of differential effects for T3 versus T4 augmentation in depressed patients free of thyroid disease. The results have implications for the treatment of depression in the presence of thyroid disease and for the mechanism of thyroid hormone potentiation of antidepressants.
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Cooke RG, Payne JH, Homeida AM. Effect of oxytocin on plasma concentrations of 13,14-dihydro-15-keto-prostaglandin F2 alpha during the oestrous cycle and early pregnancy in the goat. PROSTAGLANDINS 1991; 42:201-9. [PMID: 1780442 DOI: 10.1016/0090-6980(91)90110-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The effect of subcutaneous oxytocin on plasma concentrations of 13,14-dihydro-15-keto-prostaglandin (PG) F2 alpha (PGFM) was examined in the goat at various periods during the oestrous cycle and early pregnancy. 100 i.u. oxytocin was administered daily for 4 day, the dose being divided and given at 0900 and 2100 h; PGFM concentrations were assessed after the first treatment of each day. On days 3-6 (oestrus, day 0) PGFM concentrations increased significantly (P less than 0.001) within 15 minutes and both non-pregnant and mated goats exhibited oestrus behaviour by day 7. Significant (P less than 0.01) increases in PGFM were also produced on days 7-10, in both non-pregnant and pregnant goats, but the responses diminished from day 7 to day 10; only one goat (non-pregnant) came into oestrus. There was a marked difference in response between groups, however, during days 12-15. In non-pregnant goats significant (P less than 0.05) increases in PGFM were detected on days 13-15, but in pregnant animals oxytocin was without effect. Similarly, oxytocin did not increase PGFM concentrations on days 17-20 of pregnancy. However, uterine responsiveness reappeared in pregnant goats with significant (P less than 0.01) increases in PGFM on days 24 and 25.
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Cooke RG, Warsh JJ, Hasey GM, McLaughlin BJ, Jorna T. Epstein-Barr virus antibodies and severity of depression. Biol Psychiatry 1991; 29:621-3. [PMID: 1647225 DOI: 10.1016/0006-3223(91)90102-r] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Cooke RG. The psychiatrist and chronic fatigue syndrome. CANADA DISEASES WEEKLY REPORT = RAPPORT HEBDOMADAIRE DES MALADIES AU CANADA 1991; 17 Suppl 1E:13-5. [PMID: 1669347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Cooke RG. MS in the Faroe Islands and the possible protective effect of early childhood exposure to the "MS agent". Acta Neurol Scand 1990; 82:230-3. [PMID: 2270752 DOI: 10.1111/j.1600-0404.1990.tb01611.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Epidemiologic data on multiple sclerosis (MS) in the Faroe Islands have been interpreted by the original investigators as supporting a particular infectious disease model. They suggest that MS occurs as a late consequence of extended exposure to an infectious agent which cannot be transmitted to subjects younger than 11 years of age. However, the Faroes data may better fit an alternate model, in which MS results from delayed primary exposure to an infectious agent which more commonly produces benign illness and protection against MS in subjects who are exposed in infancy or early childhood.
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Cooke RG, Warsh JJ, Stancer HC, Hasey GM, Jorna T, Langlet F. Effect of concurrent medical illness on dexamethasone suppression test results in depressed inpatients. CANADIAN JOURNAL OF PSYCHIATRY. REVUE CANADIENNE DE PSYCHIATRIE 1990; 35:31-5. [PMID: 2317731 DOI: 10.1177/070674379003500105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A retrospective evaluation of the clinical records of 138 depressed patients, who received the dexamethasone suppression test (DST) as part of a standardized physical and psychiatric assessment protocol, revealed that 60 had acute, chronic (mild or severe), stable or remitted medical conditions. The proportion of DST nonsuppressors did not differ between depressed subjects with medical conditions (45% nonsuppressors) and those without (34.6% nonsuppressors; p greater than 0.2). However, all of the six subjects with acute or chronic-severe medical conditions were found to be nonsuppressors (p = 0.003). These results may help clarify the medical exclusion criteria for the clinical application of the DST.
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Cooke RG, Homeida AM. Effect of PGI-2 on uterine activity in vivo in non-pregnant ovariectomized goats (Capra hircus). JOURNAL OF REPRODUCTION AND FERTILITY 1989; 87:175-8. [PMID: 2516131 DOI: 10.1530/jrf.0.0870175] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Jugular administration of 200 micrograms PGI-2 salt significantly reduced spontaneous uterine activity in ovariectomized, oestrogen-primed goats; the effect was acute and persisted for about 3 h. Peripheral plasma concentrations of 6-keto-PGF-1 alpha, the stable metabolite of PGI-2, decreased to 50% of initial values after 30 min; but at the start of uterine recovery were in excess of 2 ng.ml-1. Uterine reactivity to both oxytocin and PGF-2 alpha after PGI-2 administration was unaffected.
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Essawy SA, Benhaj KM, Cooke RG, Dobson H. Effect of dose and route of administration of ACTH1-24 on plasma cortisol concentrations in ewes. J Vet Pharmacol Ther 1989; 12:302-6. [PMID: 2810480 DOI: 10.1111/j.1365-2885.1989.tb00675.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Doses of 0.005-1.0 mg of ACTH1-24 given intravenously, intramuscularly or as an intramuscular depot injection caused increases in cortisol concentrations within 15 min in the plasma of ewes. There was, however, considerable animal-to-animal variation in maximum concentrations achieved. A curvilinear dose-response relationship to ACTH1-24 was obtained which was similar for each route of administration when expressed in terms of maximum cortisol concentrations. However, for a given dose, more prolonged release of cortisol occurred after i.m. injection compared to i.v., with maximum concentrations occurring 6 h after the depot formulation injection. Five repeated daily doses of 1.0 mg depot ACTH1-24 resulted in no diminution of cortisol response indicating considerable synthesizing capacity of the adrenals in clinically normal ewes. Comparison of cortisol concentrations after an acute stressor (shearing) suggests that doses of ACTH1-24 greater than 0.25 mg are excessive for simulation of stress-induced adrenal activity.
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Cooke RG. Testosterone secretion during early pregnancy in the goat. Theriogenology 1989; 32:331-4. [PMID: 16726679 DOI: 10.1016/0093-691x(89)90323-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/1989] [Accepted: 05/06/1989] [Indexed: 11/29/2022]
Abstract
Increased peripheral concentrations of testosterone were detected on Days 12 and 13 of the estrous cycle (estrus=Day 0), at the onset of luteolysis in goats. In pregnant goats no increases in testosterone occurred between Days 10 and 18 after mating, and luteal regression was inhibited. It is suggested that testosterone is required for luteolysis in goats, and that the absence of any increase in testosterone concentrations is another manifestation of the mechanisms involved in the maternal recognition of pregnancy.
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Cooke RG, Warsh JJ, Hasey GM. Epstein-Barr virus as a cause of autoimmune disease and other medical morbidity in patients with affective disorders. Med Hypotheses 1989; 29:177-85. [PMID: 2550749 DOI: 10.1016/0306-9877(89)90192-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We hypothesize that psychiatric patients suffering from the major affective disorders (depression and manic-depressive illness) may commonly also suffer from a chronic active infection with the Epstein-Barr virus. This infection would be a consequence of the immune dysfunction known to be associated with these disorders of mood. According to this hypothesis, the increased medical morbidity and mortality reported in these psychiatric patients would be attributable in part to diseases in which Epstein-Barr virus is implicated or suspected as a cause.
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Arias TD, Inaba T, Cooke RG, Jorge LF. A preliminary note on the transient polymorphic oxidation of sparteine in the Ngawbé Guaymí Amerindians: a case of genetic divergence with tentative phylogenetic time frame for the pathway. Clin Pharmacol Ther 1988; 44:343-52. [PMID: 3416554 DOI: 10.1038/clpt.1988.160] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The oxidation of sparteine was studied in a total of 121 Ngawbé Guaymí volunteers in Panama, 97 of whom were unrelated. When presented in a frequency histogram, the results of the log10 of the metabolic ratios (LMR) indicated the existence of two modes, the largest of which exhibited a normal distribution (alpha = 0.05; chi 2 = 5.46). A preliminary assignment of an antimode for this population sample is proposed, located within the region of LMR 0.65 to 0.85 vs LMR of 1.3 for white subjects, and results in five poor metabolizers (PMs) (5.2%). This is in contrast to the absence of PMs (0/210) we have reported for the Cuna Amerindians. The microevolution of the sparteine route, corresponding to a tenfold change in the frequency of PMs, is likely to have occurred within their genetic divergence time. These observations of the divergence of a metabolic route of therapeutic importance and the proposal of a time frame for its microevolution constitute the first cases in the literature.
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Cooke RG, Benhaj KM. A possible role for testosterone during luteolysis in the ewe. Res Vet Sci 1988; 45:222-4. [PMID: 3194591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Increased peripheral plasma concentrations of testosterone were detected at the commencement of luteolysis and at oestrus in sheep. Daily subcutaneous administration of spironolactone (10 mg kg-1) between days 10 and 16 of the oestrous cycle suppressed testosterone secretion and delayed luteolysis and oestrus. In pregnant ewes no increases in testosterone concentrations occurred between days 10 to 16 after mating and luteal regression, monitored by peripheral progesterone concentrations, was inhibited. It is suggested that aromatisation of testosterone to oestrogens is needed for luteolysis in sheep.
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