EFEK KAPSAISIN TERHADAP PENYERAPAN BEBERAPA NUTRIEN DAN KADAR SEROTONIN DI USUS HALUS

• Main Author: Darwis, Moechlyar
• Format: Dissertations
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/1517
• Institution: Institut Teknologi Bandung

The purpose of this study is to determine whether or not the capsaicin contained in capsicum fruits influence the intestinal absorption of water and nutrients. Besides this, the effect of capsaicin on the activity of mucosal ATPase, serotonin content of intestinal mucosa and respiration of rat liver homogenates were also studied. Nutrient absorption investigation were carried out in Krebs-Ringer phosphate buffer, pH 7.4 in the small intestine of Wistar rats using two methods. First, in vitro method, using sacs of everted small intestine, as described by Smyth D.H., T.H. Wilson and G. Wiseman. Second, in situ perfusion method as described by Soedigdo P. from the Biochemical Laboratory of the Bandung Institute of Technology. Capsaicin was dissolved first in small amounts of absolute ethanol and then mixed with a given quantity of Krebs Ringer phosphate buffer solution. Monosaccharides were determined spectrophotometrically using the method of Nelson-Somogyi. In the in vitro experiments, L-tyrosine was determined spectrophotometrically using the method of Lowry. L-(U- 14 C)tyrosine, L-(U- 14 C)phenylalanine and L-(U- )-4 C) valine, were used in the in situ experiments and each of their concentrations was determined by means of Liquid Scintillation Counter.Intestinal mucosa ATPase was isolated by the method of Ahmed-Judah. The inorganic phosphate (Pi) as a product of ATP hydrolysis by ATPase was determined using the method of Chen and his co-workers and also by means of the method of Fiske-Subbarow. Oxygen consumtion by rat liver homogenates was determined by Warburg\\\\\\\\\\\\\\\'s respirometer method. Serotonin in the intestinal mucosa was isolated and assayed according to the method of Sidney Uden£riend. In these nutrient absorption experiments, the concentration of monosaccharides in each solution was 3 mM; that of L-tyrosine 2 mM in the in vitro experiments and 0.5 mM in the in situ experiments. It must be noted that the concentration of valine and phenylalanine were 3 mM respectively. The results of the in vitro experiments showed that the absorption of galactose into sacs of everted small intestine was inhibited by 0.1% of capsaicin for ca. 47% - 82%/60 min/100 mg wet weight. The absorption of 2 mM L-tyrosine was inhibited between 22% - 64%. The effect of capsaicin on the absorption of water was not clearly visible. The inhibition by capsaicin on the absorption of nutrients and water also occured in the in situ experiments. The absorption of the following substances were inhibited by 0.01% capsaicin viz.galactose 9 - 88%, glucose 10% - 43%, L-valin 1% - 46%, water 5% - 57%, while 3-0-methylglucose was strongly inhibited 46%-100%.If the concentration of capsaicin in the solution was decreased to 0.01%, the glucose and water were inhibited for 0.5% - 42% and 20% - 67% respectively; L-tyrosine and water for 1% - 30% and 4% - 36% respectively; L-phenylalanine and water for 6% - 29% and 6% - 39% respectively, and L-valine and water for 2% - 41% and 14% - 60% respectively. The result of the experiments showed that 0.001% - 0.01% capsaicin inhibited the activity of Na + ,K + , Mg ++-ATPase for 38% - 60%. This suspension contained 115 mM Na+ 5 5 mM K + , 5 mM Mg ++ , 30 mM Tris.HC1, pH 7.4 and 5 mM ATP. At a fixed concentration of capsaicin, which is 0.01%, the activity of Na + ,K + ,Mg ++ -ATPase was inhibited for 19% - 71%, whereas Mg ++-ATPase without Na+ ,K + , was inhibited between 39% - 89%. The addition of L-cysteine together with capsaicin solution could not reduce the inhibitory effect of capsaicin on the activity of ATPase. Even L-systeine itself inhibited the activity of ATPase. The Michaelis constant (Km ) for Na + ,K + ,Mg ++ -ATPase was determined and appeared to be (7.1 - 9.3) x 10-4 M. The type of the inhibition can be classified as \\\\\\\\\\\\\\\"Mixed Inhibition\\\\\\\\\\\\\\\". Ethanol up to 2% does not affect the absorption of glucose and neither does the activity of Na + ,K + ,Mg ++ -ATPase. It has been shown that 0.01% capsaicin reduces the mucosal serotonin content to about 8% - 41% in a perfusion experiment using 3 mM glucose.The capsaicin does not inhibit the respiration of rat liver homogenates, there is even tendency to stimulate it in the presence or in the absence of ethanol used as the solvent for capsaicin. From the results of the experiments, it can be concluded that capsaicin disturbs the absorption of water and nutrients in the small intestine. It decreases the serotonin content and the activity of the mucosal ATPase. Therefore, capsaicin contained in capsaicum is a disadvantage for nutrient absorption in the small intestine. The peristaltic reflex of the intestine is known to depend on the integrity of mucosa. Irritation by capsaicin may reduce the integrity of mucosa and may lead to miscellaneous disorders of fluid and electrolites absorption. Fluid diarheae must be the result of a defect in normal handling of fluid and electrolytes by the intestinal mucosa. This may be caused by capsaicin.