[Changes in suprachiasmatic and paraventricular hypothalamic nuclei in essential hypertension]

Suprachiasmatic and paraventricular hypothalamic nuclei (SCN and PVN, respectively) were studied in humans with essential hypertension (EH) and in healthy individuals who had normal blood pressure and died by accident (control group). Immunohistochemistry, hybridization in situ using computer image analysis have shown that EH patients have decreased number of vasopressin (VP) positive cells in SCN, high number of corticotropin-releasing hormone (CRH) producing neurones in PVN and increased amount of mRNA for CRH in them. A negative linear correlation was found between the number of CRH-producing cells in PVN, amount of mRNA for CRH in them and the number of VP-synthesizing cells in SCN. The presence of GABA in VP-producing cells in SCN together with the data obtained suggest the presence of certain "disinhibition" of CRH-producing cells in PVN in EH which could cause enhanced synthesis of ACTH in anterior hypophysis and increased secretion of corticosteroids by the adrenal gland.