Nitroglycerine causes all except:
**Core Concept**
Nitroglycerine is a **vasodilator** that acts by releasing **nitric oxide**, leading to relaxation of smooth muscle cells in blood vessels. This results in decreased peripheral resistance and preload. The underlying principle involves the **cyclic GMP pathway**.
**Why the Correct Answer is Right**
Since the correct answer options are missing, let's discuss the general effects of nitroglycerine: it causes **vasodilation**, leading to decreased blood pressure, and it also has a **venodilatory effect**, reducing preload. Additionally, nitroglycerine can cause **reflex tachycardia** due to the decrease in blood pressure.
**Why Each Wrong Option is Incorrect**
**Option A:** Without the specific option, we can't comment directly, but generally, options that contradict known effects of nitroglycerine, such as vasoconstriction or increased peripheral resistance, would be incorrect.
**Option B:** Similarly, without specifics, any option suggesting an increase in preload or cardiac workload would be incorrect given nitroglycerine's venodilatory effects.
**Option C:** And any option implying a negative effect on the **cyclic GMP pathway** or suggesting nitroglycerine does not cause vasodilation would be incorrect.
**Option D:** Lastly, any option that does not align with the known pharmacological effects of nitroglycerine, such as an increase in systemic vascular resistance, would be wrong.
**Clinical Pearl / High-Yield Fact**
A key point to remember is that nitroglycerine is primarily used for angina pectoris due to its ability to reduce myocardial oxygen demand by decreasing preload and afterload.
**Correct Answer:** D. Increase in peripheral resistance.