Acid Ulcers In Rats Research Articles

Studies on defensive factors of experimental ulcers. (Report 1) Changes in tissue components of gastric mucosa and stroma during the healing process of acetic acid ulcers in rats and effects of anti-ulcer drugs

Studies on defensive factors of experimental ulcers. (Report 1) Changes in tissue components of gastric mucosa and stroma during the healing process of acetic acid ulcers in rats and effects of anti-ulcer drugs

Studies on the mechanism of action of cetraxate [4'-(2-carboxyethyl)phenyl trans-4-aminomethyl cyclohexanecarboxylate hydrochloride], a new anti-ulcer agent.

To elucidate mechanisms involved in the anti-ulcer action of cetraxate, the effects of this agent on the ulcer index (UI), fibrinolytic activity (FA) and contents of several connective tissue components in ulcer tissue were examined using aspirin- and acetic acid ulcers in rats. In aspirin ulcer, cetraxate (100 and 300 mg/kg p.o.), like tranexamic acid (500 mg/kg p.o.), epsilon-aminocaproic acid (500 mg/kg p.o.) and gefarnate (200 mg/kg p.o.), inhibited both the UI and FA. However, aluminum sucrose sulfate (1000 mg/kg p.o.) was effective only against the UI and L-glutamine (500 mg/kg p.o.) failed to inhibit both parameters. In acetic acid ulcer, following oral, daily X either 5 or 8 administrations, cetraxate (200 and 300 mg/kg), gefarnate (200 mg/kg), aluminum sucrose sulfate (1000 mg/kg) and L-glutamine (500 mg/kg) were effective on both the UI and FA. Tranexamic acid (500 mg/kg) and epsilon-aminocaproic acid (500 mg/kg) were ineffective on the UI, although both agents inhibited FA. In acetic acid ulcer, cetraxate induced increases in hexosamine and uronic acid, that is, acid mucopolysaccharides (AMPS), especially chondroitin sulfate A and -C, whereas L-glutamine and aluminum sucrose sulfate resulted in increases in hexosamine and sialic acid, that is, glycoproteins. From these results, cetraxate may mainly accelerate the ulcer healing by increasing AMPS in ulcer tissue. Moreover, the local anti-FA property of this agent may be also beneficial in treating bleeding ulcers.

Changes in connective tissue components in ulcer tissue during the healing process of acetic acid ulcer in rats.

In order to elucidate the role of connective tissue components on the repair of ulcerated regions, quantitative changes in chemical components in ulcer tissue during the healing process were investigated in acetic acid-induced ulcer in rats. The ulcer index showed a peak on the 5th day after the operation, declined rapidly and maintained a slight level the 15th to the 60th days, without a complete recovery. In ulcer tissue, sialic acid and hexosamine remarkably increased in the early stages of healing, showing a peak on the 5th day. The patterns of time course of changes in both components ran almost parallel with those in the ulcer index. Uronic acid maintained slightly higher levels than normal levels the 5th to the 60th days. Hydroxyproline continued to increase with the time course from the 25th day. When acid mucopolysaccharides in ulcer tissue were isolated into various fractions, there were increases in hyaluronic acid on the 5th day, in chondroitin sulfate A and chondroitin sulfate C on the 30th day and chondroitin sulfate B on the 60th day, respectively. Significance of changes in these components in the healing process is discussed.

Changes in connective tissue components in ulcer tissue during the healing process of acetic acid ulcer in rats

In order to elucidate the role of connective tissue components on the repair of ulcerated regions, quantitative changes in chemical components in ulcer tissue during the healing process were investigated in acetic acid-induced ulcer in rats. The ulcer index showed a peak on the 5th day after the operation, declined rapidly and maintained a slight level the 15th to the 60th days, without a complete recovery. In ulcer tissue, sialic acid and hexosamine remarkably increased in the early stages of healing, showing a peak on the 5th day. The patterns of time course of changes in both components ran almost parallel with those in the ulcer index. Uronic acid maintained slightly higher levels than normal levels the 5th to the 60th days. Hydroxyproline continued to increase with the time course from the 25th day. When acid mucopolysaccharides in ulcer tissue were isolated into various fractions, there were increases in hyaluronic acid on the 5th day, in chondroitin sulfate A and chondroitin sulfate C on the 30th day and chondroitin sulfate B on the 60th day, respectively. Significance of changes in these components in the healing process is discussed.

Studies on the mechanism of action of cetraxate [4′-(2-carboxyethyl)phenyl trans-4-aminomethyl cyclohexanecarboxylate hydrochloride], a new anti-ulcer agent

To elucidate mechanisms involved in the anti-ulcer action of cetraxate, the effects of this agent on the ulcer index (UI), fibrinolytic activity (FA) and contents of several connective tissue components in ulcer tissue were examined using aspirin- and acetic acid ulcers in rats. In aspirin ulcer, cetraxate (100 and 300 mg/kg p.o.), like tranexamic acid (500 mg/kg p.o.), ε-aminocaproic acid (500 mg/kg p.o.) and gefarnate (200 mg/kg p.o.), inhibited both the UI and FA. However, aluminum sucrose sulfate (1000 mg/kg p.o.) was effective only against the UI and L-glutamine (500 mg/kg p.o.) failed to inhibit both parameters. In acetic acid ulcer, following oral, daily x either 5 or 8 administrations, cetraxate (200 and 300 mg/kg), gefarnate (200 mg/kg), aluminum sucrose sulfate (1000 mg/kg) and L-glutamine (500 mg/kg) were effective on both the UI and FA. Tranexamic acid (500 mg/kg) and ε-aminocaproic acid (500 mg/kg) were ineffective on the UI, although both agents inhibited FA. In acetic acid ulcer, cetraxate induced increases in hexosamine and uronic acid, that is, acid mucopolysaccharides (AMPS), especially chondroitin sulfate A and -C, whereas L-glutamine and aluminum sucrose sulfate resulted in increases in hexosamine and sialic acid, that is, glycoproteins. From these results, cetraxate may mainly accelerate the ulcer healing by increasing AMPS in ulcer tissue. Moreover, the local anti-FA property of this agent may be also beneficial in treating bleeding ulcers.

The Therapeutic Effect of FM100, A Fraction of Licorice Root, on Acetic Acid Ulcer in Rats

The Therapeutic Effect of FM100, A Fraction of Licorice Root, on Acetic Acid Ulcer in Rats