Mono- and diacylglycerol lipases in spinal cord of lean and obese Zucker rats.

1. Genetically obese Zucker rats (fa/fa) contain 2-3 times higher activities mono- and diacylglycerol lipases in their spinal cords than their lean littermates. 2. When rats were exercised (1 hr daily, 5 days/week) on a treadmill for 6 months, there was a decrease of about 30% (P less than 0.05) in the activities of mono- and diacylglycerol lipases in lean rats but not in obese animals. 3. High activities of lipases in Zucker obese rats may be related to the elevated levels of beta-endorphin present in these animals. 4. The activities of arylsulfatase, beta-N-acetylhexosaminidase and alkaline phosphatase, tested to check the stability of spinal cord extracts, were similar in lean and obese rat spinal cords.