Figure 5

Frequency distribution of labelled neurons in frontal brain sections after in situ hybridization with riboprobes against sheep 5HT2 A -receptor, according to the number of silver grains per neuron, in the premammillary hypothalamus of pinealectomized Suffolk ewes at different stages of the expression of the endogenous circannual reproductive rhythm (experiment 2). Closed and open symbols depict ewes with high or low LH pulsatile activity, respectively.