PubMed Health⌕ Search

Biomedical subjects

J Bennie

Publications and source records attributed to J Bennie.

27 records · Page 2Linked to original sources
PubMed1988

Regulation of pituitary alpha-subunit, beta-luteinizing hormone and prolactin messenger ribonucleic acid by gonadotropin-releasing hormone and estradiol in hypogonadal mice.

We have investigated the effects of three different GnRH injection regimens and the effects of estradiol benzoate (EB) on expression of the common alpha-subunit, beta-LH, and PRL genes in male and female hpg mice. GnRH was injected once daily (100 ng), every 2 h (100 ng) or every 30 min (25 ng), and EB (10 micrograms) was injected once daily. The effects of continuous exposure to the superactive agonist D-Trp6-GnRH released from microcapsules were also studied. Northern blot analysis showed that administration of GnRH increased alpha-subunit mRNA levels 2- to 10-fold in male and female hpg but not normal mice and had no significant effect on beta-LH or beta-TSH mRNA levels. The greatest increase in alpha-mRNA occurred when 100 ng GnRH were injected every 2 h and could be detected within 6 h of the first GnRH injection. More frequent injections (25 ng every 30 min) were less effective in increasing alpha-mRNA, as was prolonged exposure to the D-Trp6-GnRH superagonist. The increase in alpha-mRNA was associated with an increase in pituitary FSH content of similar magnitude. Continuous exposure of the pituitary gland to D-Trp6-GnRH (approximately 1500 ng/day) resulted in a smaller (2-fold) increase in alpha-mRNA and pituitary FSH content, suggesting that desensitization had occurred. EB had little effect on beta-LH mRNA and did not alter alpha-mRNA levels or affect the increase in alpha-mRNA caused by GnRH. Injection of GnRH every 2 h increased pituitary PRL mRNA levels in female but not male hpg mice, probably due to an indirect effect resulting from increased estrogen secretion. We conclude that GnRH administration to hpg mice significantly increases alpha-subunit but not beta-LH mRNA levels and that maximal effects occur with 100 ng GnRH injections every 2 h. Although EB does have direct effects upon pituitary gonadotropin content in hpg mice, the absence of significant changes in alpha- and beta-LH mRNA suggests that these effects may be largely posttranscriptional.

Animals↗
PubMed1987

Elevated plasma luteinizing hormone concentrations, cryptorchidism and mania.

A young man with acute mania and unilateral cryptorchidism had plasma luteinizing hormone (LH) concentrations that were much higher than the maximum LH concentrations we have found in normal subjects and patients with schizophrenia. Plasma concentrations of testosterone and sex hormone binding globulin were not abnormal, showing that the elevated plasma LH concentrations were probably due to increased secretion of LH-releasing hormone (LHRH). This case supports our previous results which suggest that an abnormally high secretion of LHRH, due presumably to an abnormality in central neurotransmission, may be a feature of acute mania in young men.

Acute Disease↗
PubMed1987

Characteristic plasma hormone changes in Alzheimer's disease.

A systematic endocrine investigation in dementia, depression and control subjects showed that plasma growth hormone (GH) was higher in the morning and plasma TSH concentrations were higher throughout the day in Alzheimer-type dementia (ATD) than in age-matched depressed patients (MDD), and plasma TSH concentrations were also higher throughout the day in female ATD compared with age-matched female control subjects. The increased plasma TSH concentrations could not be due to reduced negative feedback because plasma T3, T4 and rT3 were in the normal range. Plasma concentrations of oestrogen-stimulated neurophysin (ESN) were lower throughout the day in ATD compared with MDD and controls and lower in the morning compared with other dementias. The high plasma GH and TSH concentrations in ATD may reflect the reduced hypothalamic content of somatostatin in ATD, and the reduced concentrations of ESN may reflect reduced cholinergic activity in ATD brain. These selective hormonal changes provide a useful diagnostic test for Alzheimer's disease.

Adult↗
PubMed1987

Increased plasma LH in manic-depressive illness: evidence of a state-independent abnormality.

Basal plasma luteinising hormone concentrations and the LH responses to LH-releasing hormone injection were higher in 11 young men after recovery from mania than in 15 control subjects. Since plasma concentrations of testosterone and sex hormone binding globulin were similar in the recovered manic compared with the control subjects, the increased LH response to LHRH is likely to have been due to the priming effect of LHRH consequent on an increased release of LHRH into hypophysial portal vessel blood. Abnormal control of LHRH, and thereby LH release, is a state-independent feature in male patients with mania and may be a useful trait marker for this disorder.

Adult↗
PubMed1986

Oestrogen-stimulated neurophysin and outcome after electroconvulsive therapy.

Plasma concentrations of oestrogen-stimulated neurophysin (ESN), prolactin, and growth hormone were measured before and after the first treatment in a course of electroconvulsive therapy (ECT) given to 25 psychiatric patients and during induction of anaesthesia in 9 women undergoing elective cholecystectomy. Prolactin levels rose and growth hormone levels fell during both cholecystectomy and ECT, but ESN levels rose only after ECT. The peak ESN response to ECT was significantly greater (p less than 0.005) in the 16 depressed patients who recovered than in the 9 who did not. All patients in whom plasma ESN concentration increased by more than 100% satisfactorily recovered from their depressive illness. If a 63% increase in ESN concentration is used to classify all subjects, 12% are misclassified by outcome at 2 months. The extent of the ESN response, but not the prolactin or growth hormone responses, correlated with improvement in symptoms measured by Hamilton Rating Scale for Depression and the Montgomery and Asberg Depression Rating Scale.

Adolescent↗
PubMed1985

Selective increase in plasma luteinising hormone concentrations in drug free young men with mania.

The hypothalamic-pituitary-gonadal system was investigated in drug free young men with either mania or acute schizophrenia and in age matched controls by measuring, at frequent intervals during a 17 hour "neuroendocrine day," plasma concentrations of luteinising hormone (LH), follicle stimulating hormone, prolactin, testosterone, sex hormone binding globulin (SHBG), and cortisol. Plasma LH in mania was significantly increased compared with the control value at all time periods and increased in the morning and evening samples compared with values in the schizophrenic patients. Plasma prolactin and cortisol concentrations were significantly greater in mania and schizophrenia compared with control values at several times during the day, but there were no significant between group differences in plasma testosterone or SHBG. These results show that in young men with mania there is a major disturbance in the central mechanisms that control the release of LH, the control of prolactin and cortisol secretion is abnormal in mania and acute schizophrenia, and plasma LH concentrations may provide a useful hormonal diagnostic test for mania.

Adolescent↗
PubMedDate not supplied

Mood, cognition and cortisol: their temporal relationships during recovery from depressive illness.

Single-case methodology, using cross-lagged panel correlations, was applied to study the order of change in mood, cognition and cortisol concentration in eight in-patients with a diagnosis of major, endogenous depression. Daily measures included: two visual analogue scales measuring depressed mood and general feeling of unwellness; cortisol concentration in saliva (sampled four times a day) and in 24-h urine; two cognitive scales, the Automatic Thoughts Questionnaire and the Cognitive Style Test. The results relating to the temporal relationship between biological and psychological data were ambiguous as the pattern of change was inconsistent among individuals. Group data indicated that changes in feeling unwell preceded changes in early evening salivary cortisol and changes in negative automatic thoughts preceded changes in day and early evening salivary cortisol. Psychological variables and cortisol concentrations were generally negatively correlated within individuals indicating that over the short recovery period improving mood and cognition were associated with increasing levels of cortisol. A more consistent pattern of precedence of change was obtained for mood and cognition: negative cognitive style predicted changes in both mood measures and feeling unwell predicted changes in negative automatic thoughts.

Adult↗
PubMedDate not supplied

Sulpiride treatment of acute mania with a comparison of the effects on plasma hormone concentrations of lithium and sulpiride treatment.

Sulpiride, in this open study of acute manic patients, had a clear antimanic action with all eight patients responding to sulpiride treatment without the need for other antipsychotic drugs. Plasma prolactin concentrations were increased and oestrogen-stimulated neurophysin concentrations decreased by sulpiride but were unchanged by lithium treatment, whereas TSH concentrations showed a rapid increase following the introduction of lithium therapy.

Adult↗