Behavioral modeling: The use of chemical reaction kinetics to investigate lordosis behavior in female rats

In this paper, a model of lordosis in the female rat is proposed, based on possible neurochemical events mediating this behavior. In particular, we hypothesize that the synthesis of a specific neurotransmitter may be the rate-limiting step in the onset of lordosis behavior. Based on this hypothesis, the display of lordosis reflects the availability of this neurotransmitter. We postulate several alternative chemical reaction mechanisms to account for the synthesis of this transmitter. Behavioral testing, using ovariectomized estrogen-primed female rats, during the period immediately following progesterone injection, has enabled us to select one of these mechanisms. The implications of our model, offering a new method for studying mechanisms of behavior, are discussed.