The effects of freezing and cryoprotectant exposure on adenylate cyclase activity in cell membranes of bovine thyroid gland and adrenal cortex

We present data on the effect of freezing with or without cryoprotectant (C PA) dimtethyl suphoxide (Me2SO), as well as effects of exposure to CPA alon e on the activity of adenylate cyclase in cellular membranes of thyroid gla nds and adrenal cortex. Our results show that freezing without cryoprotecta nt increases unstimulated adenylate cyclase activity and decreases sensitiv ity to specific regulators. CPA at a concentration of 5% for adenylate cycl ase in adrenal cortex tissue and of 10% in thyroid gland allowed preservati on of the best responses to specific receptor agonists.