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PRESSOR SUBSTANCES FROM THE BODY FLUIDS OF MAN IN HEALTH AND DISEASE
1Hospital of The Rockefeller Institute for Medical Research.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Researchers identified a potent pressor substance in human bodily fluids. Its action is mediated by the central nervous system, primarily affecting splanchnic arteries, but not elevated in hypertension patients.
Area of Science:
- Physiology
- Pharmacology
- Biochemistry
Background:
- Human blood plasma, ascitic, and cerebrospinal fluids contain a substance with prolonged pressor activity.
- The substance's chemical properties suggest it is an organic base, soluble in alcohol, water, and acetone, and sensitive to heat.
Purpose of the Study:
- To characterize the pressor substance found in human bodily fluids.
- To investigate the mechanism of action of this pressor substance.
- To determine if this substance is elevated in patients with various forms of hypertension.
Main Methods:
- Extraction of the pressor substance using alcohol and chloroform.
- Testing the pressor effects in animals, including experiments involving anesthesia, pithing, and brain ablation.
- Assessing the substance's interaction with the carotid sinus reflex and peripherally acting drugs.
- Investigating the effect of adrenal gland removal on the pressor response.
Main Results:
- The pressor substance is liberated from plasma colloids upon alcohol coagulation and does not appear in ultrafiltrates.
- The pressor effect is mediated by the central nervous system, requiring functional brainstem activity and being more pronounced in unanesthetized animals.
- The substance sensitizes the carotid sinus reflex mechanism and its pressor effect is mainly due to splanchnic arterial constriction.
- No increase in the pressor substance was found in the blood or cerebrospinal fluid of patients with various types of hypertension.
Conclusions:
- A novel pressor substance, likely an organic base, exists in human bodily fluids and acts via the central nervous system.
- The substance's activity is linked to splanchnic vasoconstriction and is influenced by the integrity of the central nervous system.
- The study found no correlation between the presence of this pressor substance and common forms of human hypertension.
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