Thermal changes produced by intrahypothalamic injections of acetylcholine during hibernation and euthermia in Citellus lateralis

Major Changes in the Brain Histamine System of the Ground SquirrelCitellus lateralisduring Hibernation

“…Given these results of decreased turnover, it seems reasonable to assume that the maintenance of brain activity in the hibernation mode requires activity in these respective monoamine systems be held at a low level and that increases in the activity of these systems would trigger arousal from hibernation. Indeed, intracerebroventricular microinjections of norepinephrine Wang, 1978, 1979) and intrahypothalamic microinjections of acetylcholine (Stanton and Beckman, 1977), norepinephrine, and 5-hydroxytryptamine (Beckman and Satinoff, 1972) have been shown to induce arousal in hibernating ground squirrels. From these microinjection findings, it may again be concluded that each of these neurotransmitter systems seems to be subjected to inhibitory influence during hibernation and that arousal occurs when this inhibition ceases and the transmitter systems are reactivated.…”

Major Changes in the Brain Histamine System of the Ground SquirrelCitellus lateralisduring Hibernation

“…Given these results of decreased turnover, it seems reasonable to assume that the maintenance of brain activity in the hibernation mode requires activity in these respective monoamine systems be held at a low level and that increases in the activity of these systems would trigger arousal from hibernation. Indeed, intracerebroventricular microinjections of norepinephrine Wang, 1978, 1979) and intrahypothalamic microinjections of acetylcholine (Stanton and Beckman, 1977), norepinephrine, and 5-hydroxytryptamine (Beckman and Satinoff, 1972) have been shown to induce arousal in hibernating ground squirrels. From these microinjection findings, it may again be concluded that each of these neurotransmitter systems seems to be subjected to inhibitory influence during hibernation and that arousal occurs when this inhibition ceases and the transmitter systems are reactivated.…”

Major Changes in the Brain Histamine System of the Ground SquirrelCitellus lateralisduring Hibernation

“…Given these results of decreased turnover, it seems reasonable to assume that the maintenance of brain activity in the hibernation mode requires activity in these respective monoamine systems be held at a low level and that increases in the activity of these systems would trigger arousal from hibernation. Indeed, intracerebroventricular microinjections of norepinephrine Wang, 1978, 1979) and intrahypothalamic microinjections of acetylcholine (Stanton and Beckman, 1977), norepinephrine, and 5-hydroxytryptamine (Beckman and Satinoff, 1972) have been shown to induce arousal in hibernating ground squirrels. From these microinjection findings, it may again be concluded that each of these neurotransmitter systems seems to be subjected to inhibitory influence during hibernation and that arousal occurs when this inhibition ceases and the transmitter systems are reactivated.…”

Major Changes in the Brain Histamine System of the Ground SquirrelCitellus lateralisduring Hibernation

“…Given these results of decreased turnover, it seems reasonable to assume that the maintenance of brain activity in the hibernation mode requires activity in these respective monoamine systems be held at a low level and that increases in the activity of these systems would trigger arousal from hibernation. Indeed, intracerebroventricular microinjections of norepinephrine Wang, 1978, 1979) and intrahypothalamic microinjections of acetylcholine (Stanton and Beckman, 1977), norepinephrine, and 5-hydroxytryptamine (Beckman and Satinoff, 1972) have been shown to induce arousal in hibernating ground squirrels. From these microinjection findings, it may again be concluded that each of these neurotransmitter systems seems to be subjected to inhibitory influence during hibernation and that arousal occurs when this inhibition ceases and the transmitter systems are reactivated.…”