diff --git a/src/backend/replication/logical/applyparallelworker.c b/src/backend/replication/logical/applyparallelworker.c
index cd0e19176f..8e849af958 100644
--- a/src/backend/replication/logical/applyparallelworker.c
+++ b/src/backend/replication/logical/applyparallelworker.c
@@ -1007,7 +1007,7 @@ ProcessParallelApplyMessage(StringInfo msg)
 
 	switch (msgtype)
 	{
-		case 'E':				/* ErrorResponse */
+		case PqMsg_ErrorResponse:				/* ErrorResponse */
 			{
 				ErrorData	edata;
 
@@ -1047,8 +1047,8 @@ ProcessParallelApplyMessage(StringInfo msg)
 			 * NotifyResponse as the logical replication worker doesn't need
 			 * to send messages to the client.
 			 */
-		case 'N':
-		case 'A':
+		case PqMsg_NoticeResponse:
+		case PqMsg_NotificationResponse:
 			break;
 
 		default:
