Sains Malaysiana 30: 135-141 (2001)                                                                           Sains Hayat/

        Life Sciences

Kandungan Karnitina dalam Plasma dan Hati Tikus

Yang Diberi Suplemen Karnitina  dan Perlakuan Aflatoksin B_I

(Content of Carnitine in Plasma and Liver of Rats Supplemented with

Carnitine and Aflatoxin BI Treatment)

Ayub Mohd Yatim, Nazaruddin Ramli

Program Sains Makanan

Pusat Pengajian Sains Kimia dan Teknologi Makanan

Fakulti Sains dan Teknologi

Universiti Kebangsaan Malaysia

43600 UKM Bangi, Selangor D.E., Malaysia

Dileep S. Sachan

Department of Nutrition

College of Human Ecology

Universiti of Tennessee

Knoxville, TN 37996-1900, USA

ABSTRAK

Kesan suplemen karnitina dan dos tunggal aflatoksin B, (AFB₁) ke atas kepekatan karnitina dalam plasma dan hati tikus telah dikaji. Sebanyak 20 tikus jantan Sprague-Dawley dibahagikan kepada 4 kumpulan iaitu kumpulan kawalan (NSC), kumpulan kawalan + AFB₁ (NSA), kumpulan karnitina kawalan ICSC) dan kumpulan karnitina kawalan + AFB₁ (CSA). Tikus ini diberikan makanan tikus jenama Purina dengan 0.4% L-karnitina untuk kumpulan CSC dan CSA atau makanan tanpa karnitina untuk kumpulan NSA dan NSC selama 6 minggu. Kumpulan NSA dan CSA telah diberi dos tunggal [³H]AFB₁ (l mg/kg) 6 jam sebelum dimatikan. Didapati karnitina plasma dari haiwan yang diberi diet berkarnitina (CSC dan CSA) mempunyai karnitina tidak teresterifikasi (NEC), asilkarnitina yang tidak larut asid (AlAC) dan karnitina total (TC) yang lebih tinggi berbanding haiwan yang tidak diberi diet berkarnitina (NSC dan NSA) (P<0.05). AFB₁ tidak memberi kesan yang bererti (P > 0.05) terhadap kepekatan karnitina plasma. Bagaimanapun, di dalam hati, perlakuan AFB₁ didapati meningkatkan secara bererti fraksi-fraksi karnitina (kecuali untuk AlAC). Secara keseluruhan, penambahan karnitina dalam diet meningkatkan kandungan fraksi-fraksi karnitina dalam plasma dan hati.

ABSTRACT

The effects of carnitine supplementation and a single dose of aflatoxin B1 (AFB₁) on the concentrations of carnitine in plasma and liver of rats were investigated. Twenty male Sprague-Dawley rats were divided into four groups, namely nonsupplemented control INSC), nonsupplemented control + AFB₁ (NSA), carnitine supplemented control (CSC) and carnitine supplemented control + AFB₁ (CSA). Rats were fed Purina Rat Chow containing 0.4% L­carnitine for CSC and CSA groups or chow without added carnitine for NSA and NSC groups for 6 weeks. The NSA and CSA animals were given a single dose of [JH]AFB₁ (l mg/kg) 6 h before sacrificing. It was found that the plasma of carnitine supplemented rats (CSC and CSA) contained higher nonesterified carnitine (NEC), acid insoluble acylcarnitine (AlAC) and total carnitine than the non-supplemented rats (NSC and NSA).  AFB_I had no significant effect on plasma carnitine concentrations, but significantly increased all the carnitine fractions except for AIAC in the liver.  In conclusion, carnitine supplementation was found to increase carnitine concentrations in both plasma and liver, while AFB₁ treatment increased liver carnitine levels only.

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