True about lathyrism: PGI 09
**Core Concept**
Lathyrism is a neurolathyrism, a condition caused by the consumption of the Lathyrus sativus (grass pea) due to its toxicity. The condition primarily affects the motor neurons, leading to a degenerative disorder.
**Why the Correct Answer is Right**
The Lathyrus sativus contains a toxin called ODAP (oxalyldiaminopropionic acid), which inhibits the enzyme glutamate decarboxylase. This enzyme is crucial for the synthesis of GABA (gamma-aminobutyric acid) from glutamate. As a result, there is an accumulation of glutamate in the nervous system, causing excitotoxicity and subsequent damage to the motor neurons.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is not relevant to the pathophysiology of lathyrism.
**Option B:** Lathyrism is not caused by an allergic reaction to the grass pea.
**Option C:** This option is incorrect as lathyrism primarily affects motor neurons, not sensory neurons.
**Clinical Pearl / High-Yield Fact**
The consumption of Lathyrus sativus can also lead to anemia and other systemic symptoms due to its high content of goitrogens, which can interfere with iodine uptake in the thyroid gland.
**Correct Answer: D.**