Ornithine decarboxylase and thymidine kinase activities and polyamine levels from selected organs of adult miniature swine receiving three concentrations of dietary menhaden oil

Mature, female swine were randomly assigned to one of seven dietary groups. Swine in groups 1-3 were fed a cholesterol-rich diet for 55 days while the remaining groups remained on a basal swine diet. At the end of the cholest erol(Chol)-preloading period the swine in groups 1-7 were placed on menhade n oil (MO) and/or corn oil (CO) as follows: groups 1 and 4, 15% CO (control ); groups 2 and 5, 0.75% MO + 14.25% CO; groups 3 and 7, 15% MO; and group 6, 7.5% MO + 7.5% CO. Animals were killed at the end of the approximately 6 -month feeding period and portions of liver, pancreas and colon mucosa were analyzed for both ornithine decarboxylase (ODC) and thymidine kinase (TK) activity while polyamine levels were measured in the liver and pancreas. St atistical analyses were carried out by one-way and two-way ANOVA and by tre nd analysis. In the pancreas, the highest MO group (group 7) had significan tly higher ODC levels when compared with the CO control (group 4) and the n ext to highest MO group (group 6) (one-way ANOVA)-all non-cholesterol prelo aded groups. Using a two-way ANOVA (Chol-by-MO), liver ODC was significantl y lower in the CO control when compared with the lowest and highest MO grou ps (groups 5 and 7, respectively), again in the non-cholesterol-preloaded a nimals. In the colon, the swine in the Chol-low MO group (group 2) had sign ificantly lower TK activity than the Chol/CO control group (group 1) and Ch ol/Hi MO group (group 3) (one-way ANOVA) and also had significantly lower a ctivity than all groups except the CO control (group 4) (two-way ANOVA). Li ver acetylputrescine in the lowest and highest MO groups (groups 5 and 7, r espectively) was significantly higher than in the CO group (group 4). Liver spermidine in the Chol-Hi MO group (group 3) was significantly higher than the Chol-Lo PAO group (group 2), while the highest MO group (group 7) had a statistically higher level than the other non-cholesterol groups (groups 4-6) (one-way ANOVA). Liver spermine was significantly higher in the Chol-H i MO group (group 3) when compared to the CO control (group 1) and the Chol -Lo MO group (group 2) (one-way ANOVA). Pancreatic putrescine in the CO con trol (group 4) was significantly higher than all other groups (two-way ANOV A) while spermine from the 2 Chol-MO groups (groups 2 and 3) was higher tha n the Chol-CO control (group 1) (one-way ANOVA). Using trend analysis, live r TK, putrescine and spermidine increased in the non-cholesterol preloaded groups with increasing dietary MO, similar to the increase seen in ODC. Thu s, of the three organs studied, only liver responded to menhaden oil with c hanges in both ODC itself or some of its metabolic engendered products and thymidine kinase; at least for one of the parameters, ODC, change associate d with dietary MO was dependent on whether the swine were preloaded with ch olesterol. Published by Elsevier Science Ltd.