Rats fed linseed oil in microemulsion forms enriches the cardiac sarcoplasmic reticulum lipids with docosahexaenoic acid and lower calcium transport

The effect of feeding rats with whey protein or lipoid microemulsion of n-3 rich linseed oil (LSO), and n-6 rich sunflower oil (SNO) compared to native or microemulsion forms of each oil for 60 days on fatty acid composition, Ca2+Mg2+ ATPase, Ca2+ uptake and membrane fluidity of rat cardiac sarcoplasmic reticulum (SR) were assessed. Rats consuming LSO in lipoid microemulsion showed higher levels of ALA (18:3, n-3) conversion to DHA (22:6, n-3) when compared to rats given LSO in native form. Compared to all other dietary treatments, the alterations in the n-6/n-3 PUFA composition of SR of rats given LSO in lipoid microemulsion effected the greatest changes in Ca2+Mg2+ ATPase activity and Ca2+ uptake which effectively reduced Ca2+ transport. Therefore, the LSO in lipoid microemulsion confers similar heart healthy fatty acid compositional and calcium transport changes and potentially anti-arrhythmic effects similar to fish oils.