Uptake of glucose and cholesterol by the ovary of sheep and cattle and theinfluence of arterial LH concentrations

Time series analysis methods were used to evaluate the relationships betwee n the uptake of glucose and cholesterol, and arterial luteinizing hormone ( LH) concentrations. Classical arterio-venous difference methods were applie d to study ovarian uptake of metabolites. Arterial and venous samples (n = 20) were obtained from six cows and nine sheep every 10 min. There were hig hly significant positive cross-correlations of 0.5 for cattle and 0.8 for s heep between the uptake of glucose and cholesterol at lag 0. hll individual cross-correlations were significant for sheep. Uptake of these metabolites was not significantly associated with arterial LH concentrations in the co ws. This study suggests that glucose may promote cholesterol uptake into the ov arian cells or vice verse. This study is the first to identify such a relat ionship. If these findings are repeated, the possibility exists that contro l of the oestrous cycle and fertility may be achieved by seeking a common r egulator of uptake of these metabolites or by uncoupling the association be tween glucose and cholesterol, (C) 2000 Elsevier Science B.V. All rights re served.