Tohru Ogihara

AN ACTH-PRODUCING PITUITARY CARCINOMA DEVELOPING CUSHING'S DISEASE

An autopsy case of an ACTH-producing pituitary carcinoma in a 59-year-old man who developed Cushings disease is reported. The surgically removed pituitary tumor was diagnosed as chromophobe adenoma, however, pulmonary metastases appeared 2 years after the operation. Autopsy revealed a residual pituitary tumor in the sella turcica with systemic metastases to the lungs, liver, pulmonary lymph nodes, hypothalamus, dura mater, and the subarachnoid space of the midbrain and spinal cord. Immunohistochemistry revealed ACTH positivity in the tumor cells. Further immunohistochemical study showed positive high expression of Ki-67 in the tumor removed at surgery as well as in the autopsied tumor. Ki-67 labeling index provided valuable information about the invasive and proliferative potential compared to noninvasive benign pituitary adenoma.

Evaluation of the Renin-Angiotensin System in Diabetes Insipidus and Psychogenic Polydipsia

The role of the renin-angiotensin system in polyuric patients was studied in 5 patients with pituitary diabetes insipidus, 1 patient with nephrogenic diabetes insipidus and 3 patients with psychogenic polydipsia by determining the plasma renin activity and infusing an angiotensin II analog, 1-Sar, 8-Ile angiotensin II. In all patients with diabetes insipidus, plasma renin activity was markedly increased and the blood pressure was reduced in 5 of 6 patients by the administration of the angiotensin II analog. In the other patient, the blood pressure remained unchanged. The plasma renin activity and response of blood pressure to the angiotensin II analog in a patient with nephrogenic diabetes insipidus were not significantly different from there of patients with pituitary diabetes insipidus. On the other hand, in all patients with psychogenic polydipsia, plasma renin activity was normal or low, and the blood pressure increased with the administration of the angiotensin II analog. These results suggest that evaluation of the renin-angiotensin system by determining plasma renin activity and infusing an angiotensin II analog is useful in differentiating between diabetes insipidus and psychogenic polydipsia.

Continuous hemodiafiltration for potential amniotic fluid embolism: dramatic responses observed during a 10-year period report of three cases.

Continuous Hemodiafiltration for Potential Amniotic Fluid Embolism: Dramatic Responses Observed During a 10-Year Period Report of Three Cases To the Editor, The exact pathophysiology of amniotic fluid embolism (AFE) is unknown. Even now, no method of treatment has been established, and we are somehow managing by using combinations of symptomatic treatments. Here we report excellent efficacy of continuous hemodiafiltration (CHDF) to treat 3 cases of AFE in the past 10 years, and we would like to recommend CHDF as a treatment for the disease. Humoral factors that are removed by CHDF are suggested to play an important role in the pathophysiology of AFE, because CHDF is very effective against AFE, as we present in this report.

Direct renal action of captopril (SQ 14225): Dissociation of natriuretic and vascular actions in isolated perfused rat kidney

Direct effects of captopril on renal function were examined in isolated perfused rat kidneys. Captopril induced a significant increase in urinary volume and urinary sodium excretion (1.8- and 1.7-fold, respectively; both p less than 0.005), whereas urinary potassium excretion and renovascular resistance were not significantly changed. Because the perfusion medium lacks angiotensinogen, kininogen and aldosterone, the natriuretic action in perfused kidneys may not be related to its inhibitory action on angiotensin I converting enzyme or kininase II. Because the natriuresis was not accompanied by changes in renovascular resistance, it is suggested that captopril possesses a direct natriuretic action and that this property may partly explain the mechanism of captopril-induced natriuresis clinically observed.

Metabolism of Bradykinin in Isolated Perfused Rat Kidney Measurement of Kininase Activity in Perfusate and Urine

The effect of bradykinin and kininase on renal function and the metabolism of bradykinin in the kidney were examined in isolated perfused rat kidney. In this experimental system, exogenous bradykinin did not affect the water and electrolyte handling by the kidney. Most of bradykinin and kininase in urine were derived from kidney but not from circulating medium. Kininase II may not have a major role in bradykinin destruction by the kidney.