Also see:
Carrageenan, Inflammation, Cancer, Immunity
Carrageenan: A pseudo-latex allergy
Doubts surface about safety of common food additive, carrageenan
Carrageenan: How a “Natural” Food Additive is Making Us Sick
Jpn J Pharmacol. 1979 Aug;29(4):509-14.
Anti-inflammatory action of progesterone on carrageenin-induced inflammation in rats.
Nakagawa H, Min KR, Nanjo K, Tsurufuji S.
Effect of progesterone (1 mg/kg) on the inflammation in rats induced by carrageenin was studied. Progesterone inhibited the vascular permeability and the formation of granulation tissue in the early phase of the inflammation. In the chronic proliferative phase, progesterone suppressed the vascular permeability and there was an active resorption of the granulation tissue. Increased degradation of noncollagen protein was observed in the treated group without apparent influence on the metabolism of collagen or on the synthesis of noncollagen protein. The mode of action of progesterone was compared with that of a potent anti-inflammatory steroid, hydrocortisone acetate.
Biochemical Pharmacology Volume 30, Issue 6, 15 March 1981, Pages 639–644
Anti-inflammatory action of progesterone and its possible mode of action in rats
Nakagawa Hideo, Kyung Rak Min†, Tsurufuji Susumu
The effect of progesterone on carrageenin-induced paw edema was studied in rats. Repeated injections of progesterone (1 mg/kg body weight) were given subcutaneously every 12 hr; the swelling of the paw edema was significantly inhibited by five, seven and nine injections of progesterone, whereas three injections of progesterone caused a significant inhibition at 1 hr only after carrageenin injection into the hind paw. α1 Macroglobulin (α1 M) was purified by gel filtration on Sephadex G-200 and DEAE-cellulose column chromatography from the pooled sera of rats injected repeatedly with progesterone (1 mg/kg body weight) or the vehicle (sesame oil). The trypsin-inhibiting capacity of the α1 M fraction from the progesterone-treated group was about twice as high as that from the control group. The anti-inflammatory action of the purified α1 M from the serum of the progesterone-treated rats was studied; the swelling of carrageenin-induced paw edema was significantly inhibited for 1–2 hr after carrageenin injection, and this effect became progressively less pronounced over 3–4 hr when a single intravenous injection of the purified α1 M fraction (19 mg protein/rat) was given immediately before the carrageenin injection into the hind paw. A granuloma pouch was induced by the injection of a 2% carrageenin solution into a pre-formed air pouch on the back of rats and the purified α1 M (70 mg protein/kg body weight) was injected into the air pouch immediately after the carrageenin injection, with the result that a single injection of the purified α1 M significantly inhibited the formation of granulation tissue on day 4 after the carrageenin injection. These results suggest that progesterone exerts its anti-inflammatory action through an increased protease-inhibiting activity of α1 M, although anti-inflammatory action of the purified α1 M from vehicle-treated rat serum, alone, was not examined.