It has been suggested recently that testosterone secretion by the human testis may be controlled by factors other than luteinizing hormone (LH). In order to re-examine this hypothesis, plasma LH and testosterone concentrations were determined throughout the day in eight studies. A new method of data analysis revealed that the levels of the two hormones were closely related, but that the testicular response to LH was sluggish. These results explain some inconsistencies in the literature. It was demonstrated that average values for LH varied throughout the day, with a morning maximum and an evening minimum. It was also shown that injections of LH releasing hormone in man resulted in an increase in plasma testosterone above control levels. These results are consistent with the concept that LH controls the major changes in testosterone secretion in men. They do not exclude, however, the possible existence of other factors which might affect the peripheral concentration of testosterone, such as changes in testicular blood flow.
ALTHOUGH colchicine poisoning by accident and therapeutic misadventure is well documented, ingestion for suicidal purposes has been recorded on relatively few occasions. This paper adds two further cases to the literature. Case reports Case 1Having frequently threatened to kill herself, a 16-year-old girl ate more than a dozen flowers of Colchictim autumnale (meadow saffron) at about midday on 3 September 1967. A few hours later she developed profuse vomiting and diarrhoea, which continued throughout the night.At 10.00 a.m. the following morning she was admitted to hospital in a state of profound shock She complained of intense thirst and abdominal pain and appeared severely dehydrated. Her heart rate was 132/min and systolic blood pressure 40 mm Hg. She was hypothermic (350C) and all tendon reflexes were depressed.Investigations: Hb 17-2 g/100 ml, PCV 575/s, WBC 40,800/mm3, platelets 152,000/mm.3, blood urea 64 mg/100 ml, capillary blood pH 7T28, std. bicarbonate 18-0 mEq/l, base excess -7 mEq/l, Pco2 40 mm Hg.Urethral catheterization produced a small quantity of urine of SG 1-020. There was heavy albuminuria.Intravenous fluids were given and the acidosis corrected with sodium bicarbonate. Metaraminol and noradrenaline were infused to maintain a systolic blood pressure of 90-95 mm Hg. Gastric lavage was not performed.Despite therapy, which included atropine, vomiting and diarrhoea continued and by 4.00 p.m. she had passed only 10 ml urine, of SG 1-010. The blood urea had risen to 84 mg/100 ml, but the urine urea concentration was only 120 mg/100 ml. Her respiratory rate was now 50/min, with a minute volume
Anterior pituitary glands from male rats aged 21, 40, 60 or 95 days were incubated in medium containing 0, 2 or 20 ng luteinizing hormone-releasing hormone (LH-RH)/ml. Incubates were assayed for LH by radioimmunoassay (RIA), by the radioligand-receptor assay (RLA) using testicular homogenates as the source of receptor and, in some instances, by the ovarian ascorbic acid depletion assay (OAAD). Irrespective of the dose of added LH-RH, glands from rats aged 40 and 60 days always showed a higher release of LH, as determined by RLA, than glands from animals aged 21 or 95 days. Measurement by RIA showed a similar pattern to RLA in the basal release of LH, but in the presence of LH-RH showed little difference in LH release by glands from rats aged 40, 60 or 95 days. The LH release caused by the higher concentration of LH-RH was always greater when measured by RLA than by RIA. Assay of comparable incubates by OAAD showed close agreement with RLA estimates in four incubations (mean index of discrimination 1.07; range 0.86-1.18) and consistent disagreement with RIA estimates (1.64; range 1.38-1.99). In contrast to the results with incubates, homogenates of pituitary glands from male rats of various ages showed close agreement of estimates by RLA, RIA and OAAD. These results suggest that RIA underestimates the LH-RH-stimulated release of LH in vitro from the male rat pituitary during some stages of sexual maturation.
The specific binding of radioiodinated HCG and LH by homogenates of adult rat testes in vitro has been demonstrated by (1972).The right testis from each of three to ten rats, according to the age-group being studied, were decapsulated and homogenized in Krebs-Ringer bicarbon¬ ate buffer (KRB) using eight strokes of a loosely-fitting glass homogenizer. After filtering through cotton wool, the homogenate was centrifuged at 1500 g for 10 min and the sediment weighed and resuspended at a concentration of 40 mg/ml KRB. Incubations with [131I]hLH were carried out using 0-4 ml of this suspension in a final volume of 0-6 ml in glass vials under a 95/5 mixture of 02/C02 at 21°C. At the end of the experiment, the incubates were twice centrifuged after the addition of cold KRB, as described by Catt,
Seventeen oophorectomized women were treated for 3 month periods, in random sequence, with ethinyl oestradiol 20 and 50 mug daily and conjugated equine oestrogens (Premarin)0-625 and 1-25 mg daily. The serum cholesterol, clot lysis time, plasma fibrinogen, platelet adhesiveness and activated partial thromboplastin time remained unchanged throughout the different oestrogen regimes. There was a significant rise of serum triglyceride levels on both doses of ethinyl oestradiol but no significant change with Premarin. Serum luteinizing hormone levels were depressed most by ethinyl oestradiol 50 mug daily, although no down to the levels in premenopausal women.
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