Thesis (M.S.)--University of Michigan, 1985.

Thesis (M.S.)--University of Michigan, 1989.

Thesis (M.S.)--University of Michigan, 1984.

Thesis (M.S.)--University of Michigan, 1985.

Thesis (M.S.)--University of Michigan, 1983.

In the present study, the effects of clomiphene citrate (CC) on ovulation, ovarian growth and ovarian steroidogenesis were examined. Ovulation in rats in response to PMSG was completely blocked by administration of three daily treatments of 1.0 mg CC/rat, but was restored by administration of hCG as a preovulatory LH surge substitute. When the number of treatment days was reduced to two days, 1.0 mg of CC enhanced ovulation in response to PMSG, whereas treatment for one day with the same dose of CC did not affect ovulation. The effects of CC on ovulation appear to be dose-dependent. The effects of CC on ovarian growth were similar to the effects of CC on ovulation. The ovarian growth induced by PMSG was inhibited by high doses of CC, while a lower dose had no effect. The inhibition of ovarian growth in terms of ovarian weight by a high dose of CC was restored by hCG given as a preovulatory LH surge. Treatment duration with CC appears to have an important influence on ovarian growth. Three daily treatments with high doses of CC significantly inhibited ovarian growth. However, when the number of treatment days was reduced from three to two, the opposite results were obtained in that CC significantly stimulated ovarian growth. The effects of CC on ovarian steroidogenesis in response to PMSG were dose-dependent. A higher dose of CC significantly stimulated estradiol-17β biosynthesis. Clomiphene citrate did not show any inhibitory effects on progesterone production. Progesterone production was stimulated by hCG in CC treated rats. Lower doses of CC stimulated progesterone and androgen production. Further studies on this are necessary. Histological examination of the ovary revealed that CC selectively inhibited the development of nondominant follicles. The dominant follicles were unaffected as for they were able to develop to the mature stage. These results suggest that the effects of CC on ovulation, ovarian growth and ovarian steroidogenesis are dose-dependent and affected by treatment duration. Clomiphene citrate is assumed to exert its action via a gonadotropic mechanism. / Medicine, Faculty of / Obstetrics and Gynaecology, Department of / Graduate

La dégradation photoinduite du Monuron (herbicide) a été étudiée dans trois systèmes différents produisant des radicaux hydroxyle : en présence du complexe Fe(III)Cit, dans une suspension de TiO2 et dans un système combiné Fe(III)Cit / TiO2. Le but principal était d'améliorer l'efficacité photocatalytique. La spéciation et la photoactivité du complexe ont été déterminées en fonction du pH. La cinétique de dégradation du Monuron photoinduite par le complexe se fait en deux étapes avec deux sources successives de radicaux °OH : 1) photolyse du complexe ; 2) cycle photoredox du fer. La présence de TiO2 améliore l'efficacité du système Fe(III)Cit à pH acide alors qu'à pH neutre l'efficacité du système est complètement inhibée. La concentration en oxygène et le pH sont les facteurs clés en présence du complexe Fe(III)Cit. De plus, dans un système pilote utilisant du TiO2, l'influence d'un solvant organique lors de la dégradation du 4-chlorophénol en milieu aquatique a été examinée.

Thirty-eight female Wistar rats were studied to determine the response of citrate synthase (CS) and glycogen (GLY) to two similar programs of endurance training. Animals were randomly assigned to one of three groups: run-trained (RUN), swim-trained (SWIM) or sedentary control (CON). The treadmill trained animals ran at a speed of 27 m/min. up an eight degree incline. The swim-trained animals swam with 2% of body weight attached to their tails. The duration of the exercise protocols was 2 hours/day, the frequency 5 days/week and the length of the training regimen was 10 weeks. Liver GLY content (mmoles/g) for the exercise trained groups was significantly higher (p < 0.01) than CON. There were no significant differences between RUN and SWIM animals in the GLY levels of the hindlimb muscles. The GLY levels of the forelimb muscles were significantly greater (p0.01) in the SWIM animals compared to the RIJN animals, apart from the pectoralis (EEC). The CS activity in the soleus (SOL) and red -vastus (RV) of the RUN animals was significantly larger (p <; 0.01) than SWIM. The plantaris (PLANT) of the SWIM animals had significantly greater CS activity than the RUN animals. In the forelimb muscles, only -the deltoid (DEL) of the SWIM group was higher in CS activity than the RUN groups. The results of this study indicate that the mechanisms responsible for increased GLY storage in skeletal muscle are under independent control to those factors governing the changes in the oxidative enzyme CS. Differences in muscle GLY levels and CS activity between RUN and SWIM rats can be explained by contrasting mechanics in these two (nodes of exercise and the resulting fiber recruitment patterns.

Many of the physiological responses concomitant with exercise are understood. Similarly, many of the changes characterizing the aging process have been established. However, the combination of the two (ie. effects of aging on exercise or vice versa) presents a myriad of questions, of which many remain unanswered.The objective of this study was to establish the differences between previously untrained young and adult male Fischer 344 rats following an exhaustive swim for the following parameters: 1) muscle glycogen, an essential fuel substrate; 2) Glucose-6-phosphate dehydrogenase (G6PDH), a marker of inflammation and tissue damage; 3) citrate synthase (CS), an integral enzyme of the Kreb's cycle and a respiratory chain marker; 4) muscle protein; and 5) percent muscle dry weight.The rats were divided into two groups by age. Young (3 mo., n=16) and adult (12 mo., n=17) rats were randomly divided into sedentary (young sed (YSD) n=7 and adult sed (ASD) n=9) or exercised groups (young swimmers (YSW) n=8 and adult swimmers (ASW) n=8). Rats in the swimming groups were given a brief exposure to the water one week prior to their exhaustive swim to minimize the stress and confusion during the actual exercise bout. On the study days one randomly selected swimmer from each age group was swum to exhaustion and sacrificed via pneumothorax. One animal from each of the respective sedentary age groups was also randomly selected and sacrificed as above. The plantaris, rectus femoris, red vastus, soleus, triceps, and liver were surgically excised from each animal and frozen in liquid nitrogen for later analysis.While the younger animals had lower glycogen stores initially, following the exhaustive swim their reduction in muscle glycogen was approximately 150% that of the adult animals for any given muscle. Muscle glycogen levels in ASD and YSD rats were significantly higher than those of the YSW animals for all muscles with the exception of the YSD's soleus. However, the percent decrease in liver glycogen following the swim for the two age groups was almost identical (a reduction of 55.05% and 58.59% for the adult and young age groups, respectively).Although the adult animals were significantly heavier than the younger rats, this did not appear to cause a significant difference in their swim time to exhaustion. No significant differences were observed between the groups for muscle protein or G6PDH. Levels of CS were significantly higher in the YSD plantaris when compared to the ASW. Similarly, the ASD rectus femoris CS levels were significantly greater than those of the ASW. Although significant differences between groups in percent muscle dry weight existed for the plantaris, rectus femoris, and triceps such differences seemed to have little bearing on the two age group's swim to exhaustion times.On the basis of this study it was concluded that although starting with greater glycogen stores prior to exercise, adult animals use less of this substrate prior to exhaustion than do younger animals. While the mechanism for such a phenomenon was not discovered it is believed to be enzymatic in nature. Furthermore, the adult animals do not appear to exhibit significantly more tissue damage following an exhaustive swim than that seen in younger animals. / School of Physical Education

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