Rodent Hormone-Nerve Interaction

Cross references: 
Rodent 5-HT1R     Rodent 5-HT3R       Serotonin Gate (5-HT3R)    
Serotonin Metabotropic Receptor          
Vasopressin, Serotonin & Aggression

Neurochemical modulation of sensory-motor reactivity: acoustic and tactile startle reflexes. 
Only the abstract is available online.  I got the PDF from the library. 
    This 1979 review lacks the results of more modern research tools and is primarily focused on the effects of therapeutic drugs.  However, it also contains useful information on the earlier research on hormones and neurotransmitters.  Most of the research was done on rodents. 
    "The present review argues that the startle reflex is particularly well suited as a model system to analyze how drugs alter stimulus reactivity and reflex excitability. It then reviews all the literature to date on how drugs or lesions that are thought to alter neurochemical transmitter systems affect acoustic and/or tactile startle.  Hypotheses are presented to account for how serotonin, dopamine, norepinepbrine, acetylcholine, and opiates modulate
    "A considerable amount of data leads to the conclusion that serotonin (5-HT) exerts a tonic inhibitory effect on startle and probably stimulus reactivity in general, since depletion of 5-HT is associated with increased startle." 
    There is then a long discussion of the effects of serotonin supplementation and depletion without any specification of the receptors involved.