Given the task definition and input, reply with output. Given a passage, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

Sphingosine 1-phosphate is a naturally occurring biologically active lysophospholipid. Recent studies suggested that sphingosine 1-phosphate is released into the blood flow from activated platelets upon stimulation to exert multiple biological phenomenon. The purpose of this study was to assess the effects of sphingosine 1-phosphate on sinus automaticity, ventricular contraction and coronary blood flow.', 'The canine isolated, blood-perfused sinoatrial node and papillary muscle preparations were used.', 'Sphingosine 1-phosphate increased the sinoatrial rate, while it decreased the coronary blood flow, which was followed by a weak negative inotropic effect. These positive chronotropic and coronary vasoconstrictor effects were not attenuated by the beta- and alpha-adrenoceptor antagonists atenolol and prazosin, respectively. Furthermore, sphingosine 1-phosphate did not affect the adenylate cyclase activity of the membrane preparations made from the canine right atrium and right ventricle, indicating the involvement of a novel signaling pathway in sphingosine 1-phosphate-induced cardiac effects.
Does sphingosine 1-phosphate induce sinus tachycardia and coronary vasoconstriction in the canine heart?