Department of Zoology, University of British Columbia, Vancouver, BC, Canada V6T 1Z4
Department of Biology, University of Massachusetts, Dartmouth, MA 02747, USA.
J Exp Biol. 2018 Oct 10;221(Pt 19):jeb186957. doi: 10.1242/jeb.186957.
We conducted inflations of freshly excised ventral aortas of the Greenland shark, , and used pressure-diameter data to estimate the point of transition from high to low compliance, which has been shown to occur at the mean blood pressure in other vertebrates including fishes. We also determined the pressure at which the modulus of elasticity of the aorta reached 0.4 MPa, as occurs at the compliance transition in other species. From these analyses, we predict the average ventral aortic blood pressure in to be about 2.3-2.8 kPa, much lower than reported for other sharks. Our results support the idea that this species is slow moving and has a relatively low aerobic metabolism. Histological investigation of the ventral aorta shows that elastic fibres are present in relatively low abundance and loosely connected, consistent with this aorta having high compliance at a relatively low blood pressure.
我们对格陵兰睡鲨的新鲜离体腹主动脉进行了膨胀，并利用压力-直径数据来估计从高顺应性到低顺应性的转变点，在包括鱼类在内的其他脊椎动物中已经证明该点出现在平均血压处。我们还确定了主动脉的弹性模量达到 0.4 MPa 的压力，这在其他物种的顺应性转变中也会出现。通过这些分析，我们预测 的平均腹主动脉血压约为 2.3-2.8 kPa，远低于其他鲨鱼的报告值。我们的结果支持这样一种观点，即这种物种行动缓慢，有氧代谢相对较低。对腹主动脉的组织学研究表明，弹性纤维的含量相对较低，连接松散，这与该主动脉在相对较低的血压下具有高顺应性一致。
