Status of the hypothalamo-hypophyseal system in patients with diffuse toxic goiter

Disorder of function of the hypothalamus-thyroid system in patients with diffuse toxic goiter is accompanied by change of the hormonal activity of the hypothalamohypophyseal-adrenocortical and hypothalamohypophyseal-ovarian systems. It is particularly marked in persons with heredity aggravated by thyroid diseases or/and diabetes mellitus.     

Reaction of the thyroid gland to a single and prolonged administration of prolactin

A study was made of the thyroid and hypophysis response to the administration of a summary analogous dose of prolactin injected in a single dose or in the course of 5 days. Experiments were made on female rats at the diestrus stage. The content of thyroid hormones and thyrotropic hormone (TTH) in the blood was determined by radioimmunoassay. The concentration of thyroid hormones and TTH was compared in the basal state and 30, 60, 120 and 180 min after prolactin injection. An acute prolactin administration was shown to result in an elevated TTH level on the 30th minute and T4 on the 60th minute. Five-day hyperprolactinemia caused a decrease in the content of thyroid hormones in the blood and disturbed positive correlative interrelationships between the thyroid hormones and negative ones between thyroxine and TTH. It is assumed that the preservation of a high prolactin level in the blood can maintain the hyperthyroid state.     

Characteristics of the clinical picture, hormonal status and humoral immunity in older patients with diffuse toxic goiter

Radioimmunoassays, immunological and radioreceptor methods were used for a study of the levels of T3, T4, TSH, thyroglobulin, antibodies to thyroglobulin and microsomal antigen, immunoglobulins suppressing thyrotropin binding in 92 patients with diffuse toxic goiter aged over 50. There was discrepancy between the prevalence of severe types of disease in this group of patients and an insignificant rise of T3 and T4 levels. Changes in the immune status pointed to an increase in immunodeficiency which became progressive with aging of the organism, and increasing sensitivity to damaging agents.     

Ultrastructure of neurons and glial cells in the solitary tract nucleus and in the ventrolateral sections of the rat medulla oblongata after subdiaphragmatic vagotomy

Using electron microscopy, complex remodelling of neuronal and glial cell ultrastructure was demonstrated in the solitary tract nucleus and ventrolateral medulla at different time intervals following bilateral subdiaphragmatic truncal vagotomy. Four weeks after vagotomy phagocytizing microgliocytes were demonstrated in the vicinity of nuclei of degenerating neurons within the rostral, but not the caudal, areas of solitary tract nucleus and ventrolateral medulla. It is suggested that the ultrastructural changes observed in the medulla after vagotomy depend on the distribution pattern of vagal projections to the caudal brainstem.     

Changes in the ultrastructure of the rat bulbar nuclei caused by kainic acid administration

The effect of kainic acid (KA) injection into the commissural area of nucleus tractus solitarii (NTS) of rats was studied to evaluate its influence on the ultrastructure of neurons and gliocytes at the site of injection and in the ventrolateral medulla (VM). 30 min after KA injection, in the perikarya of neurons in rostral and caudal NTS and VM the increased number of ribosomes, lysosomes, lipofuscin granules and edema of mitochondria were noted. Giant mitochondria were found in terminals and axons of myelin fibers. 14 days after KA injection, the increased volume of Golgi complex cisterns was found in single neurons in NTS rostral parts, while the neurons of caudal NTS demonstrated pronounced degenerative and destructive changes. During this period, the volume of mitochondria and of vacuoles was increased in dendrites within caudal NTS and VM, where degenerating processes of the nervous cells were found. In gliocytes of caudal NTS, the hypertrophy of cytoplasm was noted with the accumulation of dilated cisterns of endoplasmic reticulum and redistribution of nuclear chromatin. In the same areas of NTS the reaction of endotheliocytes and pericytes, perivascular edema and accumulation of microgliocytes were found. The results obtained indicate the reactive changes in VM in response to intracentral injection of neurotoxin.