Increased number of myocardial voltage-gated Ca2+ channels and unchanged total β-receptor number in long-term streptozotocin-diabetic rats

Gøtzsche LB-H, Rosenqvist N. Grønbœk H, Flyvbjerg A, Gøtzsche O. Increased number of myocardial voltage-gated Ca2+ channels and unchanged total β-receptor number in long-term streptozotocin-diabetic rats. Eur J Endocrinol 1996;134:107–13. ISSN 0804–4643. In order to elucidate further the abnormal myocardial Ca+ metabolism in diabetes mellitus, voltage-gated Ca2+ channels and β-receptors were quantified in myocardial membranes of short- and long-term diabetic rats. Diabetes was induced by an injection of streptozotocin (STZ). Animals were killed 2, 4, 7, 90 and 200 days after STZ. A group of diabetic animals were treated with insulin for 20 days following 180 days of untreated diabetes. Diabetic animals developed low triiodothyronine syndrome. During short-term diabetes, the maximum binding capacity (MBC) for Ca+ channels was reduced by 25% at day 4 p