Effect of pinealectomy on daily rhythm of blood glucose in rabbits.

Daily rhythm of blood glucose was studied in superior cervical ganglionectomized (SCGX), sham operated and normal rabbits. A typical daily rhythm was observed in normal animals which was not influenced by surgical procedures. However, ganglionectomy, which tantamount to physiological elimination of pineal gland, caused complete reversal of this rhythm. Probable role of pineal gland in controlling blood glucose daily rhythm is suggested.