Is the level of cyclic AMP in the pyloric caeca of the starfish Asterias rubens related to the reproductive cycle?

Abstract

1. 1. Cyclic AMP levels were significantly higher (P = 0.01) in female than in male animals. The average difference found was 0.50 pmole/mg dry weight.

2. 2. Cyclic AMP levels were negatively correlated to the pyloric caeca-index. In females this correlation was −0.54 (P < 0.05).

3. 3. Cyclic AMP levels in the females paralleled the stages of the reproductive cycle. The level was significantly lower in stage II than in stage I and stage IV by 1.98 and 2.33 pmole/mg dry weight, respectively. The physiological significance of this pattern is discussed.

4. 4. Cyclic AMP levels in male animals suggest a subdivision of the reproductive cycle into three stages. During the spermatogenic stage, cyclic AMP levels are significantly lower than in the other stages. The average differences found were 1.01 and 1.52 pmole/mg dry weight.