An immunofluorescent method for identification of isolated thyrotropic cells

A sensitive and specific immunofluorescent method for identification of thyrotropic cells was developed. The TSH-producing cells were found to be heterogenic in their morphology and intensity of staining.

Suppression of prolactin and thyrotropin secretion in the rat by antiserum to thyrotropin-releasing hormone

Administration of antiserum to synthetic thyrotropin-releasing hormone (TRH) to male and female rats cause a 50% and a 70% suppression in serum levels of prolactin and thyrotropin, respectively, as compared with controls injected with normal rabbit serum. The degree of suppression was similar in diestrous and proestrous female rats and in male rats. These findings support the view that, in addition to its original designation, TRH also has a physiological role in regulating release of pituitary prolactin.

[New methods in the treatment of weather sensitivity]

Changing weather fronts produce severe changes of daily rhythms. Electrical impulses arrive 1-2 days before the weather and create either atmospherics or "positive ions". They are responsible for the epidemic appearance of migraine and of thrombo-embolism. The impact of atmospheric electricity has been assessed in 1000 patients by daily urinalysis of serotonin, 5-HIAA, adrenaline, noradrenaline, histamine, thyroxine, 17-KS, 17-OH, Na, K, creatinine and diureses. The changes found in these 12 parameters allowed a classification of heat reactions into three clinical entities: 1. serotonin hyperproduction causing a typical irritation syndrome: 2. adrenal deficiency producing a typical exhaustion syndrome; 3. hyperthyroidism "Forme fruste" with subclinical "apathetic" thyroid symptoms. These sufferings, typical for Föhn, Tramontana, Sirocco, Sharkiye, Chamssin, Sharav and Santa Ana Winds, are mainly due to positive ionisation of the air. They can be prevented by negative ionising apparatuses or specific drug treatment.

Adenyl cyclase activity at different environmental temperatures in the isolated rat anterior pituitary membranes

The effect of different environmental temperatures on adenyl cyclase was studied. An increase in temperature appears to increase TRH-induced activity of adenyl cyclase, and possible causes an increases sensitivity to the hormone. Cyclic AMP levels of the pituitaries showed change at different environmental temperatures.

Pituitary-thyroid interrelationship in rats exposed to different environmental temperatures

The present work intended to show interrelationships between triiodothyronine (T3), thyroxine (T4), thyroid stimulating hormone (TSH) and cyclic adenosine 3'5'-monophosphate (cyclic AMP) in both the pituitary and the thyroid. Experiments were carried out on animals exposed to 0 and 37 degrees C for 4 days and to 34 degrees C for 21 days. Control animals were maintained at 22 degrees C. T4 serum levels of 2.6, 4.0 1.1 and 0.42 mug/100 ml serum, and T3 levels of 95, 135, 65 and 36 ng/100 ml serum were recorded at 22, 0, 34 and 37 degrees C, respectively. The observed serum TSH levels were 265, 192, 237 and 182 mug/100 ml serum in rats exposed to 22, 0, 34 and 37 degrees C, respectively. Pituitary TSH content was similar at 22, 0 and 34 degrees C whereas the content in the 37 degrees C exposed rats was twice that of controls. Thyroid cyclic AMP levels were not significantly different among the various experimental groups. The content of cyclic AMP in the pituitary was higher at 34 degrees C by 125% and 37 degrees C by 240%, and lower at 0 degress C by 56% with regard to the control. These results suggest that the 0 and 34 degrees C exposed rats reach a new steady state in the control of thyroid hormones secretion rate. However, at 37 degrees C, the TSH-Thyroxine interrelationships seem to break down.

Effect of air ionization of blood serotonin in vitro

The effect of negative and positive air ionisation on siliconized blood serotonin was studied in vitro. The experiments showed that within 10 min positive ionisation increased serotonin levels in total blood (+40%), plasma (+90%), erythrocytes (+50%) and thrombocytes (+240%). On the other hand, negative ionization (10 min) lowered the serotonin content of total blood (-30%), plasma (-42.5%), erythrocytes (-41.7%) and thrombocytes (-72.3%), thus confirming the 'Krueger Effect' in vitro.

Dehydroepiandrosterone-induced thyrotrophin release during heat stress in rats

Six groups each of 12 male albino rats were reared from day 21 of life at temperatures of 23, 34 or 37 degrees C. While the rats survived for unlimited periods at 23 and 34 degrees C, the animals reared at 37 degrees C succumbed within 5 days to heat stress. The latter group, when injected s.c. or i.p. with 50 mg dehydroepiandrosterone (DHA)/kg/day were no longer affected by the heat. During this treatment thyroid epithelial cell height doubled, colloid decreased by 20%, connective tissue did not change, the basic metabolic rate decreased by 10% and rectal temperatures of the treated rats increased with the ambient temperatures. Body weight increased only slightly, pituitary TSH decreased by 25%, serum TSH increased by over 50%, thyroxine and 125I uptake increased by 200%. The survival of the DHA-treated rats was apparently secured by blocking the hypothalamic thermoreceptors.

Intermittent hyperthyreosis -- a heat stress syndrome

Intermittent hyperthyreosis occurs under various forms of stress, especially heat stress. The clinician may diagnose such cases as masked or apathetic hyperthyroidism or "forme fruste" hyperthyreosis or thyroid autonomy. As most routine and standard tests may here yield inconsistent results, it is the patients' anamnesis which may provide the clue. Our Bioclimatology Unit has now seen over 100 cases in which thyroid hypersensitivity towards heat was the most prominent syndrome: 10-15% of weather-sensitive patients are affected. The patients complain before or during heat spells of such contradictory symptoms as insomnia, irritability, tension, tachycardia, palpitations, precordial pain, dyspnoe, flushes with sweating or chills, tremor, abdominal pain or diarrhea, polyuria or pollakisuria, weight loss in spite of ravenous appetite, fatigue, exhaustion, depression, adynamia, lack of concentration and confusion. Determination of urinary neurohormones allows a differential diagnosis, intermittent hyperthyreosis being characterized by three cardinal symptoms: 1. tachycardia -- every case with more than 80 pulse beats being suspect (not specific); 2. urinary histamine -- every case excreting more than 90 mug/day being suspect. Again the drawback of this test is its lack of specificity, as histamine may also be increased in cases of allergy and spondylitis; 3. urinary thyroxine -- every case excreting more than 20 mug/day T-4 being suspect. This is the only specific test. Therapy should make use of lithium carbonate and beta-blockers. Propyl thiouracil is rarely required.