Projections of the midlateral posterior hypothalamic area influencing cardiorespiratory function in rats.
The influence of the midlateral posterior hypothalamic area (MLPHA) on arterial blood pressure and respiration was examined in the rats. Electrical stimulation produced a rapid transient increase in blood pressure and rapid shallow respiration. Glutamate, which stimulates neurons and not fibers of passage, however, caused a fall in blood pressure and slowing of respiration. Projections of MLPHA traced by horseradish peroxidase (HRP) and 3H leucine showed reciprocal connections with limbic forebrain centers but only indirect connections with brainstem cardiorespiratory centers. It is concluded that MLPHA may be a relay through which the limbic system can gain access to and depress cardiorespiratory function.
Hinrichsen
C F
CF
Department of Anatomy, University of Tasmania, Hobart, Australia.
D000818:Animals; D001794:Blood Pressure; D001931:Brain Mapping; D001933:Brain Stem / Q000502:physiology; D004558:Electric Stimulation; D007031:Hypothalamus / Q000502:physiology*; D007034:Hypothalamus, Posterior / Q000502:physiology*; D008032:Limbic System / Q000502:physiology; D008297:Male; D009412:Nerve Fibers / Q000502:physiology; D009434:Neural Pathways / Q000502:physiology; D051381:Rats; D012119:Respiration