Leptin responses to long-term cardiorespiratory exercise training without concomitant weight loss: a prospective study.

AIM: The aims of the present study were to examine 1) whether changes in circulating leptin levels occur in response to six months of aerobic exercise training (ET) without concomitant weight loss; 2) whether there is a different response with respect to gender; and 3) the relationship between age and leptin and whether this relationship has any impact on the response to ET without weight-loss. METHODS: Thirty-eight healthy, sedentary men and women (age 38.43+/-2.24, range 18-59 years) participated in 6 months of supervised, moderate intensity (ET) performed 4 days per week. Maintenance of usual dietary practices were encouraged to minimize weight-loss. Participants were evaluated for circulating fasting leptin, body mass, body fat percentage and maximal aerobic power (VO2max) prior to and after ET. RESULTS: There was no decrease in body weight or leptin concentration (17.69+/-2.67 vs 16.85+/-3.12 ng dL(-1)). Gender did not affect the response to exercise training. The bivariate correlation between leptin and age was not significant, but the relationship reached significance after controlling for body fat percentage and VO2max (r = -0.358, P < 0.05). Age did not affect the response of leptin concentration to ET. CONCLUSION: It is probable that changes in leptin concentration reported previously with ET may be attributable to concomitant weight loss, but age does not play a role in how leptin responds to ET.

Fallopian tube occlusion in rabbits with silicone rubber.

A new system for transcervically blocking the Fallopian tubes with cured-in-place silicone rubber has great potential for fertility control. Good retention, antifertility efficacy, and retrievability were observed in rabbits, and no adverse tissue reactions were seen in oviducts containing silicone elastomer. Continuing studies with rabbits and rhesus monkeys attempt to determine long term efficacy and histologic changes.

The antifertility effect and improved tolerance of copper bearing hydrogel coated intrauterine devices in rabbits.

PIP: Polyethylene IUDs covered with hydrogel over copper wire were tested in 20 New Zealand white rabbits. None of the rabbits with copper-bearing hydrogel-coated IUDs became pregnant as compared with 86.6% of the sham-operated controls and 38.5% of those with only hydrogel-coated IUDs. 50% of the hydrogel-coated IUDs with copper were expelled; no fragmentation of either copper or hydrogel was seen. The total white blood cell count in uterine fluid was increased 68.1% by copper-bearing hydrogel-coated IUDs. It is concluded that hydrogel coating of copper IUDs enhances tolerance of the devices, improves the contraception, and reduces the expulsion rate. Copper diffusion from the hydrogel-coated IUD was 37.5 mcg/ml.^ieng

The effect of the polyethylene intrauterine device on peritoneal fluid cell distribution of adult female mice.

PIP: At Hahnemann Medical College and Hospital in Philadelphia, researchers attempted to determine whether uterine cavity IUD-induced inflammation extends into the abdominal cavity. Adult female mice were used. In each experimental animal (14), a piece of polyethylene intramedic tubing (1.3 cm long) was fixed in place by suture within each uterine horn. In the sham-operated controls (15), a silk suture was sutured into each horn. 3 weeks later peritoneal fluid specimens were obtained from the 2 groups and compared. The IUD resulted in significant increases in histiocytes (pl.001) and polymorphonuclear leukocytes (pl.001). Mesothelial cells were significantly decreased (pl.001), but mesothelial cells were somehwat higher in the controls than is usually found. No significant changes in lymphocytes or monocytes were observed. Only experimental animals showed daisy cells. Thus, the IUD resulted in a definite abdominal inflammatory effect. Judging by the spontaneous activity measured on an Electronic Activity Monitor, the IUD produced no animal discomfort. 25% of the IUDs were expelled.^ieng