PTPRZ1 and epilepsy: While previous studies have shown that aggrecan Cat-315-positive molecules increase from day 2 to 7 after status epilepticus in pilocarpine-induced epilepsy model rats [43] and phosphacan-positive PNNs decrease in the kainic acid-induced epilepsy model [44], neither of these studies looked at changes in Cat-315-positive PNNs.