Shinzaburo Ohtake

A New Method for Extraction of Extravasated Dye in the Skin and the Influence of Fasting Stress on Passive Cutaneous Anaphylaxis in Guinea Pigs and Rats

A method for quantitative extraction of extravasated dye from the skin was studied in guinea pigs and rats. A simple method with a low cost and good recovery was established as follows; A piece of the skin containing extravasated dye was soaked overnight in a stoppered glass tube containing 1 ml of 1 n KOH at 37 C. Then, 9 ml of a mixed solution of 0.6 n H3PO4 and acetone (5:13) was added to the tube. The tube was shaken vigorously for a few seconds and centrifuged at 3,000 rpm for 15 min. Absorbance of supernatant was measured at 620 nm. The recovery rate of the dye was about 95% both in guinea pigs and rats.

Chronic hypertension induced by streptozotocin in rats

SummaryAn intravenous injection of 40 or 65 mg/kg streptozotocin induced not only diabetes but also severe hypertension in rats. Whereas the hyperglycemia developed fully within a few days after the injection of streptozotocin, the hypertension progressively advanced and reached maximum level several weeks after the treatment and lasted more than 20 weeks. Twenty mg/kg streptozotocin did not induce hyperglycemia but significantly increased blood pressure several weeks after the treatment. Arrest of growth, polyuria, glycosuria, hyperlipemia and lenticular cataracts developed in the animals treated with 40 or 65 mg/kg streptozotocin, but in none of the animals treated with 20 mg/kg. In histological examinations in the 24th week after the treatment, degranulation and necrosis in the pancreatic β-cells, and vacuolization and deposition of PAS-positive materials in the renal proximal tubules were found in the animals treated with 40 or 65 mg/kg streptozotocin.