Presence of endothelin-1 and endothelin-3 in peripheral tissues and central nervous system of the pig.
The distribution of endothelin (ET) peptides in the pig was studied in a variety of tissues using selective radioimmunoassays combined with reverse-phase high performance liquid chromatography (HPLC). The levels of ET-like immunoreactivity (LI) were overall relatively low. The highest levels of ET-LI were found in blood vessels, cerebral and coronary arteries containing 3190 +/- 910 and 1330 +/- 450 fmol/g, respectively. Veins generally contained higher levels of ET-LI per tissue weight than corresponding arteries. Peripheral sympathetic and sensory ganglia contained a higher concentration of ET-LI than the studied central nervous system (CNS) areas. In the CNS the highest concentration of ET-LI was found in a non-neuronal structure, the choroid plexus. The levels of ET-LI were also relatively high in the respiratory tract (100-400 fmol/g). In the heart, the endocardium contained the highest levels (190 +/- 44 fmol/g). In the kidney, the concentration of ET-LI was 3-fold higher in the medulla than in the cortex. In the gastrointestinal tract all levels were below 100 fmol/g, except for the colon which contained 120 +/- 50 fmol/g. The characterization of ET-LI in extracts of some of these tissues revealed that ET-1 dominated in the lung, spleen and hypothalamus while ET-3 and ET-1 were present in approximately equal amounts in renal medulla and thoracic spinal cord. The HPLC analysis provided no clear-cut evidence for significant presence of vasoactive intestinal contractor, ET-2 or big ET-1(1-39) in the lung, spleen, kidney, spinal cord or hypothalamus. It is concluded that mature ET-1 and ET-3 are the predominant ET peptides in peripheral tissues and CNS.
Hemsén
A
A
Department of Pharmacology, Karolinska Institutet, Stockholm, Sweden.
Lundberg
J M
JM
D000818:Animals; D001808:Blood Vessels / Q000737:chemistry; D002490:Central Nervous System / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D016232:Endothelins / Q000032:analysis*; D007107:Immune System / Q000737:chemistry; D009206:Myocardium / Q000737:chemistry; D009417:Nerve Tissue / Q000737:chemistry; D011863:Radioimmunoassay / Q000379:methods; D012137:Respiratory System / Q000737:chemistry; D013552:Swine; D014018:Tissue Distribution; D014566:Urogenital System / Q000737:chemistry
D016232:Endothelins